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History of Metrohm IC – Part 5

History of Metrohm IC – Part 5

by | Jan 18, 2021 | Company

In the fifth part in our ongoing series about the history of ion chromatography development at Metrohm, we now focus on automated air quality monitoring with the 2060 MARGA instrument.

Did you miss the other parts in this series? Find them here!

History of Metrohm IC – Part 1
History of Metrohm IC – Part 2
History of Metrohm IC – Part 3
History of Metrohm IC – Part 4

The importance of clean air cannot be understated. Air pollution is one of the major environmental risks to human health; it can cause strokes, heart disease, lung cancer, and both chronic and acute respiratory diseases. Additionally, the contribution of such pollution to climate change is of significant scientific interest.

Monitoring air quality is of increasing concern, and thankfully more and more companies are taking responsibility for their input and looking for ways to measure and mitigate their environmental contribution.

What is MARGA?

MARGA (Monitor for AeRosols and Gases in ambient Air) was developed in the 1990s by Metrohm Process Analytics in cooperation with the Energy Research Centre of the Netherlands (ECN) (Figure 1).

Figure 1. The original MARGA 1S air monitoring system, developed in the 1990s by Metrohm Process Analytics.

This instrument application offered a new approach in which gases and aerosols sampled from the same air mass are separated from each other by selectively dissolving them in water. The resulting solutions (available every hour) are then analyzed using ion chromatography with conductivity detection. Separating the two fractions from each other allows for the detection of important precursor gases and ionic species found in the aerosols.

Collection of water-soluble ions and analysis by ion chromatography:
  • Gases: HCl, HNO3, HNO2, SO2, NH3
  • Aerosols: Cl–, NO3–, SO42-, NH4+, Na+, K+, Ca2+, Mg2+, *F–

*also possible with the 2060 MARGA (Figure 2)

This new analyzer application was a huge success at that time. However, in the meantime Metrohm Process Analytics was busy implementing more modular flexibility to their process analyzers. That’s why in 2018, based on the all-new 2060 online analysis platform from Metrohm Process Analytics, the 2060 MARGA (Figure 2) was introduced.

To learn more about how MARGA is used in real life situations, download our free technical notes on the Metrohm website.

Download free technical notes for MARGA here!
Figure 2. The Metrohm Process Analytics solution to unattended, automated air quality analysis: the 2060 MARGA M.

Featuring state of the art 2060 software to automate analysis 24/7, brand new hardware adaptable for modular flexibility, and the dependable and well-known MagIC Net software, the 2060 MARGA is the right solution to gain insight of the effects of particulate matter on health and the environment. This instrument is available in two versions:

2060 MARGA M (Monitoring)

The 2060 MARGA M (Figure 2) is ideal for unattended routine monitoring at a permanent site.

Everything is packed into a single instrument, with separate subcabinets for the sample collection wet part, ion analysis cabinet (with two IC channels and column oven for anion and cation determinations), plus reagent containers with level sensors.

2060 MARGA R (Research)

A flexible version, ideal for research applications, features the 2060 user interface and sample collection wet part.

Sample analysis is carried out on a stand-alone Metrohm 940 Professional IC Vario TWO/SeS/PP, including sequential suppression for the anion analysis channel. Installed on-site for a limited time campaign, the 2060 MARGA R works unattended in the same way as the 2060 MARGA M. When not required for field use, the 940 Ion Chromatograph can be put to work in the laboratory, using an external PC and MagIC Net, to run any of the multitude of applications available from Metrohm.

Figure 3. The 2060 MARGA offers hourly data and easy to read trend charts for a full overview of gas and aerosol analysis.

The 2060 MARGA is designed for monitoring in remote locations but it’s never far from home. By using a direct internet connection, the 2060 MARGA performance can be checked remotely, adjustments can be made, and results can be evaluated at any time.

Monitoring air quality around the world

MARGA systems from Metrohm have been used by many official agencies and research organizations globally to monitor air quality in a completely autonomous way.

Figure 4. World map showing the locations of installed MARGA instruments from Metrohm Process Analytics.
Scotland

The MARGA participated in a program focusing on measurement and evaluation of the long-range, transboundary transmission of air-polluting substances in Europe (European Monitoring and Evaluation Programme, «EMEP»). 

This research was performed in Auchencorth Moss, approximately 20 kilometers south of Edinburgh in Scotland, with the objective of analyzing to what degree crops and natural ecosystems, as well as the rural population, are exposed to airborne pollutants.

Learn more about this application here.

Aerosols without borders: Investigating long-range aerosol transport in Scotland
Netherlands

Fireworks are full of water-soluble ions and trace metals. The different colors are produced through the combustion of these chemical compounds. After combustion, the air is full of toxic gases and particles which can linger for a significant time, depending on weather patterns.

The 2060 MARGA can determine detailed gas and aerosol concentrations on an hourly basis completely autonomously, offering valuable scientific information about the effect of fireworks on local air quality (Figure 5).

Figure 5. Air pollution due to New Year’s Eve fireworks celebrations in the Netherlands: aerosol concentrations of selected compounds.

For more information about this application, download our free technical note here.

The completely automated MARGA system for monitoring air quality

If you would like to read more scientific literature featuring the MARGA, please download our free overview: Air monitoring with ion chromatography: An overview of the literature references.

Air monitoring with ion chromatography: An overview of the literature references

Download our free monograph:

Practical Ion Chromatography – An Introduction

Click here!

Post written by Andrea Ferreira (Technical Writer at Metrohm Applikon, Schiedam, The Netherlands) and Dr. Alyson Lanciki (Scientific Editor at Metrohm International Headquarters).

Introduction to Analytical Instrument Qualification – Part 2

Introduction to Analytical Instrument Qualification – Part 2

by | Jan 11, 2021 | Company, Evaluating results, Fundamentals

Welcome back to our blog, and happy 2021! We hope that you and your families had a safe and restful holiday season. To start the year, we will conclude our introduction to Analytical Instrument Qualification. 

Did you miss Part 1? Click here to read it first!

Introduction to AIQ: Part 1

Metrohm’s approach to Analytical Instrument Qualification (AIQ)

Metrohm’s answer to Analytical Instrument Qualification is bundled in our Metrohm Compliance Services. The most thorough level of documentation offered for AIQ is the IQ/OQ.

Metrohm IQ/OQ documentation provides you with the required documentation in strict accordance to the major regulations from the USP, FDA, GAMP, and PIC/S, allowing you to document the suitability of your Metrohm instruments for your lab’s specific intended use.

With our test procedures (described later in more detail), we can prove that the hardware and software components function correctly, both individually and as part of the system as a whole. With Metrohm’s IQ/OQ, you are supported in the best possible way to integrate our systems into your current processes.

Our high quality documentation will have you «audit ready» all the time.

Metrohm Compliance Services

The flexibility of a modular document structure

Depending on the environment you work in and your specific demands, Metrohm can offer a tailored qualification approach thanks to documentation modularity. If you need a lower level of qualification, only the required modules can be executed. Our documentation consists of different modules, each of which documents the identity of the Metrohm representative along with the qualification reviewer, combined with the details of each instrument, software, and document involved in the qualification.  Thanks to this, each module is independent, which guarantees both full traceability and reliability for your system setup.

Cost-effective qualification from Metrohm

Metrohm supports you by implementing a cost-effective qualification process, depending upon your requirements and the modules needed. This means that a qualification is not about performing unnecessary actions, qualification is about completing the required work.

The risk assessment analysis defines the level of qualification needed and based on it, we focus on testing only what needs to be tested. In case you relocate your device to another lab, which qualification steps (DQ, IQ, OQ, PQ) are really needed in order to fulfill your requirements? Contact your local Metrohm expert for advice on this matter.

A complete Metrohm IQ/OQ qualification includes…

Metrohm IQ/OQ documentation is based on the following documentation tree, beginning with the first module, the Master Document (MD), followed by the Installation Qualification (IQ) and eventually the Operational Qualification (OQ). The OQ is then divided again into individual component tests (Hardware and Software) and a holistic test to validate your complete system.

Master Document (MD)

Each qualification starts with the Master Document (MD) – the central organizing document for the AIQ procedures. It not only describes the process of installing and qualifying the instruments, but also the competence and education level of the qualifying engineer. The MD identifies all other components to be added to the qualification, resulting in a flexible framework on which to build up a set of documentation.

Installation Qualification (IQ)

Once the content of the documentation is defined in the MD, the Installation Qualification (IQ) follows. This set of documentation is designed to ensure that the instrument, software, and any accessories have been all delivered and installed correctly. The IQ protocol additionally specifies that the workplace is suitable for the analytical system as stipulated by Metrohm.

Operational Qualification (OQ)

After a correct installation comes the main part of the qualification: the Operational Qualification (OQ). In the first part of the OQ, the functionality of the single hardware components is tested and evaluated according to a set of procedures. This is to ensure that the instrument is working perfectly as designed, and is safe to use. Rest assured that you can rely on the expertise of our Metrohm certified engineers to conduct these comprehensive tests on your instruments using the necessary calibrated and certified tools.

The second part of the OQ consists of a set of Software Tests to prove that the installed Metrohm software functions correctly and reliably on the computer it was installed on. The importance of maintaining software in a validated state is also related to the data integrity of your laboratory. Therefore these software tests can be repeated periodically or after major changes. In particular, these functionality tests cover verifications on user management, database functionalities, backups, audit trail review, security policy, electronic signatures, and so on.

At Metrohm, we constantly work to improve our procedures and use state of the art tools and technologies.  For this reason, we have implemented a completely automated test procedure for validating the software of our new OMNIS platform. This ensures full integrity in the execution and delivers consistent results with a faster and completely error-free test execution. This innovative and automated software validation eliminates manual activities that are labor intensive and time consuming. This therefore expedites testing and removes the inefficiencies that plague the paper-based software validation.

Your benefit is clear: save valuable time and reduce unnecessary laboratory start-up activities during qualification. That’s time you can spend on other work in your lab!

Holistic Test (Performance Verification, PV)

Once each individual component has been separately tested, the performance of the system as a whole is proven by means of a holistic test (OQ-PV).

This includes a series of «wet-chemical» tests, performed using certified reference materials, to prove the system is capable of generating quality data, i.e. results that are accurate, precise, and above all fit for purpose. Based on detailed, predefined instructions (SOPs), a series of standard measurements are performed, statistically evaluated, and compared to the manufacturer’s specifications.

Differences between Performance Verification (PV) and Performance Qualification (PQ)

The Performance Verification (PV) is a set of tests offered by Metrohm in order to verify the fitness for purpose of the instrument. As mentioned in the previous paragraph, the PV includes standardized test procedures to ensure the system operates as designed by the manufacturer in the selected environment.

On the other hand, the Performance Qualification (PQ) is a very customer specific qualification phase (see the «4 Q’s» Qualification Phases found in Part 1). PQ verifies the fitness for purpose of the instrument under actual condition of use, proving its continued suitability. Therefore, PQ tests are defined depending on your specific analysis and acceptance criteria.

Now my questions to you—is your analytical instrument qualified for its intended use? Is your lab in compliance with the latest regulations for equipment qualification and validation? Get expert advice directly from your local Metrohm agency and request your quote for Metrohm qualification services today!

Check out our online material:

Metrohm Quality Service

Click here!

Post written by Lara Casadio, Jr. Product Manager Service at Metrohm International Headquarters, Herisau, Switzerland.

«Analyze This»: 2020 in review

«Analyze This»: 2020 in review

by | Dec 14, 2020 | Analysis, Company, Evaluating results, Fundamentals, Lab hacks, Sample preparation, Sampling

I wanted to end 2020 by thanking all of you for making «Analyze This» – the Metrohm blog for chemists such a success! For our 60th blog post, I’d like to look back and focus on the wealth of interesting topics we have published this year. There is truly something for everyone: it doesn’t matter whether your lab focuses on titration or spectroscopic techniques, or analyzes water samples or illicit substances – we’ve got you covered! If you’re looking to answer your most burning chemical analysis questions, we have FAQs and other series full of advice from the experts. Or if you’re just in the mood to learn something new in a few minutes, there are several posts about the chemical world to discover.

We love to hear back from you as well. Leaving comments on your favorite blog posts or contacting us through social media are great ways to voice your opinion—we at Metrohm are here for you!

Finally, I wish you and your families a safe, restful holiday season. «Analyze This» will return on January 11, 2021, so subscribe if you haven’t already done so, and bookmark this page for an overview of all of our articles grouped by topic!

Subscribe here!

Stay healthy, and stay curious.

Best wishes,

Dr. Alyson Lanciki, Scientific Editor, Metrohm AG

Quickly jump directly to any section by clicking a topic:

Customer Stories

We are curious by nature, and enjoy hearing about the variety of projects where our products are being used! For some examples of interesting situations where Metrohm analytical equipment is utilized, read on.

From underwater archaeological research to orbiting Earth on the International Space Station, Metrohm is there! We assist on all types of projects, like brewing top quality beers and even growing antibiotic-free shrimp – right here in Switzerland.

Interested in being featured? Contact your local Metrohm dealer for details!

Titration

Metrohm is the global market leader in analytical instruments for titration. Who else is better then to advise you in this area? Our experts are eager to share their knowledge with you, and show this with the abundance of topics they have contributed this year to our blog.

Find articles about manual titration and reproducibility, as well as why to consider automation, how to transfer manual titrations to automated methods and the time and cost savings this can offer a laboratory.

For more in-depth information about obtaining the most accurate pH measurements, take a look at our FAQ about pH calibration or read about avoiding the most common mistakes in pH measurement. You may pick up a few tips!

Choose the best electrode for your needs and keep it in top condition with our best practices, and then learn how to standardize titrant properly. Better understand what to consider during back-titration, check out thermometric titration and its advantages and applications, or read about the most common challenges and how to overcome them when carrying out complexometric titrations. 

If you are interested in improving your conductivity measurements, measuring dissolved oxygen, or the determination of oxidation in edible fats and oils, check out these blog posts and download our free Application Notes and White Papers!

Finally, this article about comprehensive water analysis with a combination of titration and ion chromatography explains the many benefits for laboratories with large sample loads. The history behind the TitrIC analysis system used for these studies can be found in a separate blog post.

Karl Fischer Titration

Metrohm and Karl Fischer titration: a long history of success. Looking back on more than half a century of experience in KFT, Metrohm has shaped what coulometric and volumetric water analysis are today.

Aside from the other titration blog posts, our experts have also written a 2-part series including 20 of the most frequently asked questions for KFT arranged into three categories: instrument preparation and handling, titration troubleshooting, and the oven technique. Our article about how to properly standardize Karl Fischer titrant will take you step by step through the process to obtain correct results.

For more specific questions, read about the oven method for sample preparation, or which is the best technique to choose when measuring moisture in certain situations: Karl Fischer titration, near-infrared spectroscopy, or both?

Ion Chromatography (IC)

Ion chromatography has been a part of the Metrohm portfolio since the late 1980s. From routine IC analysis to research and development, and from stand-alone analyzers to fully automated systems, Metrohm has provided IC solutions for all situations. If you’re curious about the backstory of R&D, check out the ongoing series about the history of IC at Metrohm.

Metrohm IC user sitting at a laboratory bench.

Common questions for users are answered in blog posts about IC column tips and tricks and Metrohm inline ultrafiltration. Clear calculations showing how to increase productivity and profitability in environmental analysis with IC perfectly complement our article about comprehensive water analysis using IC and titration together for faster sample throughput.

On the topic of foods and beverages, you can find out how to determine total sulfite faster and easier than ever, measure herbicides in drinking water, or even learn how Metrohm IC is used in Switzerland to grow shrimp!

Near-Infrared Spectroscopy (NIRS)

Metrohm NIRS analyzers for the lab and for process analysis enable you to perform routine analysis quickly and with confidence – without requiring sample preparation or additional reagents and yielding results in less than a minute. Combining visible (Vis) and near-infrared (NIR) spectroscopy, these analyzers are capable of performing qualitative analysis of various materials and quantitative analysis of a number of physical and chemical parameters in one run.

Our experts have written all about the benefits of NIR spectroscopy in a 4-part series, which includes an explanation of the advantages of NIRS over conventional wet chemical analysis methods, differences between NIR and IR spectroscopy, how to implement NIRS in your laboratory workflow, and examples of how pre-calibrations make implementation even quicker.

A comparison between NIRS and the Karl Fischer titration method for moisture analysis is made in a dedicated article.

A 2-part FAQ about NIRS has also been written in a collaboration between our laboratory and process analysis colleagues, covering all kinds of questions related to both worlds.

Raman Spectroscopy

This latest addition to the Metrohm family expands the Metrohm portfolio to include novel, portable instruments for materials identification and verification. We offer both Metrohm Raman as well as B&W Tek products to cover a variety of needs and requirements.

Here you can find out some of the history of Raman spectroscopy including the origin story behind Mira, the handheld Raman instrument from Metrohm Raman. For a real-world situation involving methamphetamine identification by law enforcement and first responders, read about Mira DS in action – detecting drugs safely in the field.

Mira - handheld Raman keeping you safe in hazardous situations.

Are you looking for an easier way to detect food fraud? Our article about Misa describes its detection capabilities and provides several free Application Notes for download.

Process Analytics

We cater to both: the laboratory and the production floor. The techniques and methods for laboratory analysis are also available for automated in-process analysis with the Metrohm Process Analytics brand of industrial process analyzers.

Learn about how Metrohm became pioneers in the process world—developing the world’s first online wet chemistry process analyzer, and find out how Metrohm’s modular IC expertise has been used to push the limits in the industrial process optimization.

Additionally, a 2-part FAQ has been written about near-infrared spectroscopy by both laboratory and process analysis experts, which is helpful when starting out or even if you’re an advanced user.

Finally, we offer a 3-part series about the advantages of process analytical technology (PAT) covering the topics of process automation advantages, digital networking of production plants, and error and risk minimization in process analysis.

Voltammetry (VA)

Voltammetry is an electrochemical method for the determination of trace and ultratrace concentrations of heavy metals and other electrochemically active substances. Both benchtop and portable options are available with a variety of electrodes to choose from, allowing analysis in any situation.

A 5-part series about solid-state electrodes covers a range of new sensors suitable for the determination of «heavy metals» using voltammetric methods. This series offers information and example applications for the Bi drop electrode, scTrace Gold electrode (as well as a modified version), screen-printed electrodes, and the glassy carbon rotating disc electrode.

Come underwater with Metrohm and Hublot in our blog post as they try to find the missing pieces of the ancient Antikythera Mechanism in Greece with voltammetry.

If you’d like to learn about the combination of voltammetry with ion chromatography and the expanded application capabilities, take a look at our article about combined analysis techniques.

Electrochemistry (EC)

Electrochemistry plays an important role in groundbreaking technologies such as battery research, fuel cells, and photovoltaics. Metrohm’s electrochemistry portfolio covers everything from potentiostats/galvanostats to accessories and software.

Our two subsidiaries specializing in electrochemistry, Metrohm Autolab (Utrecht, Netherlands) and Metrohm DropSens (Asturias, Spain) develop and produce a comprehensive portfolio of electrochemistry equipment.

This year, the COVID-19 pandemic has been at the top of the news, and with it came the discussion of testing – how reliable or accurate was the data? In our blog post about virus detection with screen-printed electrodes, we explain the differences between different testing methods and their drawbacks, the many benefits of electrochemical testing methods, and provide a free informative White Paper for interested laboratories involved in this research.

Our electrochemistry instruments have also gone to the International Space Station as part of a research project to more efficiently recycle water on board spacecraft for long-term missions.

The History of…

Stories inspire people, illuminating the origins of theories, concepts, and technologies that we may have become to take for granted. Metrohm aims to inspire chemists—young and old—to be the best and never stop learning. Here, you can find our blog posts that tell the stories behind the scenes, including the Metrohm founder Bertold Suhner.

Bertold Suhner, founder of Metrohm.

For more history behind the research and development behind Metrohm products, take a look at our series about the history of IC at Metrohm, or read about how Mira became mobile. If you are more interested in process analysis, then check out the story about the world’s first process analyzer, built by Metrohm Process Analytics.

Need something lighter? Then the 4-part history of chemistry series may be just what you’re looking for.

Specialty Topics

Some articles do not fit neatly into the same groups as the rest, but are nonetheless filled with informative content! Here you can find an overview of Metrohm’s free webinars, grouped by measurement technique.

If you work in a regulated industry such as pharmaceutical manufacturing or food and beverage production, don’t miss our introduction to Analytical Instrument Qualification and what it can mean for consumer safety!

Industry-focused

Finally, if you are more interested in reading articles related to the industry you work in, here are some compilations of our blog posts in various areas including pharmaceutical, illicit substances, food and beverages, and of course water analysis. More applications and information can be found on our website.

Food and beverages
All of these products can be measured for total sulfite content.

Oxidation stability is an estimate of how quickly a fat or oil will become rancid. It is a standard parameter of quality control in the production of oils and fats in the food industry or for the incoming goods inspection in processing facilities. To learn more about how to determine if your edible oils are rancid, read our blog post.

Determining total sulfite in foods and beverages has never been faster or easier than with our IC method. Read on about how to perform this notoriously frustrating analysis and get more details in our free LC/GC The Column article available for download within.

Measuring the true sodium content in foodstuff directly and inexpensively is possible using thermometric titration, which is discussed in more detail here. To find out the best way to determine moisture content in foods, our experts have written a blog post about the differences between Karl Fischer titration and near-infrared spectroscopy methods.

To determine if foods, beverages, spices, and more are adulterated, you no longer have to wait for the lab. With Misa, it is possible to measure a variety of illicit substances in complex matrices within minutes, even on the go.

All of these products can be measured for total sulfite content.

Making high quality products is a subject we are passionate about. This article discusses improving beer brewing practices and focuses on the tailor-made system built for Feldschlösschen, Switzerland’s largest brewer.

Pharmaceutical / healthcare

Like the food sector, pharmaceutical manufacturing is a very tightly regulated industry. Consumer health is on the line if quality drops.

Ensuring that the analytical instruments used in the production processes are professionally qualified is a must, especially when auditors come knocking. Find out more about this step in our blog post about Analytical Instrument Qualification (AIQ).

Moisture content in the excipients, active ingredients, and in the final product is imperative to measure. This can be accomplished with different analytical methods, which we compare and contrast for you here.

The topic of virus detection has been on the minds of everyone this year. In this blog post, we discuss virus detection based on screen-printed electrodes, which are a more cost-effective and customizable option compared to other conventional techniques.

Water analysis

Water is our business. From trace analysis up to high concentration determinations, Metrohm has you covered with a variety of analytical measurement techniques and methods developed by the experts.

Our blog offers articles from the basics like improving your conductivity measurements and measuring dissolved oxygen to more involved topics including comprehensive water analysis by combining titration, IC, and direct measurement in one system.

Learn how to increase productivity and profitability in environmental analysis laboratories with IC with a real life example and cost calculations, or read about how one of our customers in Switzerland uses automated Metrohm IC to monitor the water quality in shrimp breeding pools.

If heavy metal analysis is what you are interested in, then you may find our 5-part series about trace analysis with solid-state electrodes very handy.

Unwanted substances may find their way into our water supply through agricultural practices. Find out an easier way to determine herbicides in drinking water here!

Water is arguably one of the most important ingredients in the brewing process. Determination of major anions and cations along with other parameters such as alkalinity are described in our blog post celebrating International Beer Day.

All of these products can be measured for total sulfite content.
Illicit / harmful substances

When you are unsure if your expensive spices are real or just a colored powder, if your dairy products have been adulterated with melamine, or fruits and vegetables were sprayed with illegal pesticides, it’s time to test for food fraud. Read our blog post about simple, fast determination of illicit substances in foods and beverages for more information.

Detection of drugs, explosives, and other illegal substances can be performed safely by law enforcement officers and first responders without the need for a lab or chemicals with Mira DS. Here you can read about a real life training to identify a methamphetamine laboratory.

Drinking water regulations are put in place by authorities out of concern for our health. Herbicides are important to measure in our drinking water as they have been found to be carcinogenic in many instances.

Post written by Dr. Alyson Lanciki, Scientific Editor at Metrohm International Headquarters, Herisau, Switzerland.

Introduction to Analytical Instrument Qualification – Part 2

Introduction to Analytical Instrument Qualification – Part 1

by | Dec 7, 2020 | Company, Evaluating results, Fundamentals

When talking about the subject of Analytical Instrument Qualification (AIQ), my first thought is of regulated industries, like pharmaceuticals and food. 

You may be wondering—Why do we need to qualify analytical instruments in this environment? Why does my titrando or my OMNIS system need such a service?

Consumer safety here is of paramount importance. Medicines that may represent a health hazard for patients or do not provide the intended therapeutic effect are undesirable and costly, therefore steps must be taken to safeguard the manufacturing process and prevent fatal implications. By qualifying the used analytical instruments, we can ensure that active ingredients and finished pharmaceutical products are manufactured in a safe environment.

In addition, procedures that prove instrument accuracy and repeatability are a must. Metrohm qualification procedures provide this documentation, fully traceable evidence which is also required for inspections and audits by regulatory authorities.

When auditors come knocking

In case an auditor observes any violations of the United States Food and Drug Administration (FDA) guidelines for example, this will be communicated in an inspectoral observation or a Warning Letter. If we look to pharmaceutical Warning Letters in the past, we can see that the FDA is mainly concerned with issues related to qualification and data integrity.

Some typical findings are e.g. the usage of an unqualified system, or the use of an instrument outside of the calibration range for which it was initially qualified. This proves the point that qualification of analytical instruments in regulated environments cannot be ignored.

Metrohm Compliance Services can help to prove the full data traceability of your qualification activities, simplifying your audit preparation and at the same time maintaining a constant state of inspection readiness for your laboratory.

Brochure: Analytical Instrument Qualification - Confidence in quality with IQ/OQ

Instruments in regulated environments need to be qualified periodically according to the main regulatory bodies. The United States Pharmacopeia (USP) is the leading pharmacopeia that has a general chapter dedicated to Analytical Instrument Qualification (AIQ), USP <1058>. Therefore, it has global significance, making laboratories subject to regulatory requirements either directly or indirectly. This is why Metrohm Compliance Services are based on this important chapter.

What is Analytical Instrument Qualification (AIQ) exactly?

As per USP <1058>, it is «the collection of documented evidence that an instrument performs suitably for its intended purpose.» This indicates that AIQ is the foundation for generating quality data with the needed data integrity. By using qualified instruments, you gain confidence in the validity of generated data and that your instrument meets specifications of regulatory standards.

AIQ is not a single activity, but a continuous process over the lifetime of the instrument. AIQ already starts before the instrument purchase with the formal writing of User Requirement Specifications (URS), where the lab’s requirements for a specific instrument are documented. And yes, for e.g. a fully equipped Metrohm Dual IC system as well as for a single Metrohm pH meter, there is the same need to document the laboratory requirements and its intended use.

After clarification of the intended use and the evaluation of the right technology, a Risk Assessment (RA) needs to be carried out to determine the required qualification strategy to prove the «fitness for purpose» of the purchased analytical instrument.

The extent of the next qualification stages depends on the outcome of the Risk Assessment. The following activities are grouped into four phases: Design Qualification (DQ), Installation Qualification (IQ), Operational Qualification (OQ), and Performance Qualification (PQ), the so-called «4 Q’s».

Whereas the DQ is the documented verification that the instrument specifications meet the laboratory requirements, the IQ provides the proof that the equipment has been installed properly. In the OQ phase, it’s demonstrated that the system operates correctly in the selected environment as per manufacturer specifications, while the PQ confirms that the instrument consistently performs according to your defined specifications.

During the lifecycle of the instrument, major repairs might be needed, it might be subject to major updates / upgrades, or it might even be transferred to another lab. In all of these cases, the original URS should be reviewed again and adjusted if necessary. The URS is a living document that can and must be changed and updated when needed. Based on a risk assessment analysis, it will then be defined what the qualification steps are that should be repeated after the needed changes (IQ, OQ, PQ).

Eventually the instrument’s life comes to an end, and we arrive at its retirement. This final step of the AIQ is often considered as the «forgotten child» of validation activities. To put this a bit more in perspective, consider when you make a new electronic purchase, such as a PC. The situation is similar to when a new analytical system is bought. It’s easier to focus on something new—concentrating on getting the training for its proper usage, and making sure it’s working correctly. We begin to ignore or forget that the old system is still there.

Therefore, decommissioning of an instrument is a critical part of the validation process that must also be very well documented. For the old system, a final system qualification might be necessary if required. Afterwards, all data have to be removed and stored in a safe location. It is extremely important to ensure that the data can be read from this location (data migration) for a number of years, depending on your retention procedures.

Support when and where you need it

The fact that users have responsibilities for the instrument qualification (USP <1058>) does not mean that all qualification activities must be conducted alone!

Metrohm supports you over the lifetime of your investment, from advising you during the purchase process to the first installation and qualification. Additionally, our IQ/OQ documentation provides you the required documentation in strict accordance with the current regulations. To ensure your Metrohm device remains in a qualified state, we offer requalification services at scheduled intervals as specified in your requirements, to guarantee the accuracy and precision of your system over its lifetime. 

An advantage of relying on Metrohm as the manufacturer of your analytical instruments is that we have all the necessary experience for performing IQ/OQ procedures. Most importantly, our certified service engineers bring along all calibrated and certified reference instruments that are required for the qualification. To ensure the quality of Metrohm Service is maintained, our service engineers undergo compulsory re-training on a regular basis according to a globally standardized program.

Buying Metrohm equipment is the first step to success, but maintaining it in a qualified state is the key! Just contact your local Metrohm dealer and let us handle the rest.

For more details about which qualification phases can be fully handled by Metrohm and where we can support you, read Part 2!

Read Part 2 here

Check out our online material:

Metrohm Quality Service

Click here!

Post written by Lara Casadio, Jr. Product Manager Service at Metrohm International Headquarters, Herisau, Switzerland.

Electrochemistry in orbit

Electrochemistry in orbit

by | Nov 30, 2020 | Analysis, Company

For over twenty years now, there has been continuous human occupation off our planet.

The International Space Station (ISS), launched in 1998, is a modular satellite in low orbit around the Earth, which is visible even with the naked eye.

Since November 2, 2000, the ISS has had a constantly revolving crew from a variety of nations, working on projects to further push the boundaries of our knowledge. Aside from their important scientific duties, these astronauts must live their daily lives like us – exercising, relaxing, cleaning, and sleeping – albeit in microgravity.

The International Space Station celebrated 20 years of constant habitation in November, 2020.

In October, an Antares rocket carrying a Cygnus resupply ship was launched by NASA at Johnson Space Center. This cargo ship carried an experimental system on board used to study the oxidation of ammonia under microgravity conditions to convert urine into water on the ISS.

Watch the launch of the Antares rocket here!

Improving this waste management system has far-reaching repercussions for longer exploratory missions where the weight of the payload must be optimized with the amount of water needed (which is heavy) to sustain life during the trip. Given the limited resources aboard a spaceship, the recovery of water from all processes is of great importance.

Future missions which may benefit from this study include trips to the moon (Artemis) and eventually to Mars (Orion).

This system uses Metrohm DropSens screen-printed electrodes (SPEs). The novel nanomaterial coating of the electrodes was developed by researchers at the University of Alicante in Spain in collaboration with the University of Puerto Rico. In this article, we would like to introduce the people behind the project and elaborate on the research they are doing in space with Metrohm products.

Meet the researchers

Dr. José Solla Gullón (Ph.D. 2003, Chemistry)

Dr. José Solla Gullón in his laboratory at the University of Alicante, with Metrohm DropSens and Metrohm Autolab products on the bench.

I am currently a Distinguished Researcher at the Institute of Electrochemistry of the University of Alicante, Spain. My research mainly focuses on the synthesis, characterization and electrochemical properties of different types of nanoparticles with well-defined size, composition, shape, and surface structure. My overall publication record includes about 175 publications (h-index 53). I have also given more than 250 contributions in international and national meetings.

Ms. Camila Morales Navas

Camila Morales Navas holding the Nanoracks 2U, where the electrochemical equipment is kept inside.

I am a senior graduate student in the Department of Chemistry at University of Puerto Rico (UPR). I am working on a research project in collaboration with NASA, titled «Elucidating the Ammonia Electrochemical Oxidation Mechanism via Electrochemical Techniques at the ISS», or «Ammonia Electrooxidation Lab at the ISS (AELISS)» for short. The purpose of this project is to improve the water processing system and to identify new technology for long-term missions in space.

The project is attributed to NASA-ESPCoR, University of Puerto Rico, University of Alicante, NuVant Systems, and Nanoracks, with support from Metrohm DropSens.

Read more about the project on the NASA website:

Read about AELISS on nasa.gov
AELISS on the NASA blog

The AELISS project

For a brief overview by Camila and her graduate advisor, have a look at the video provided below by NASA:

Here, you can see the Metrohm DropSens instruments used for this study: the screen-printed carbon electrode (SPCE, 8X110) and its corresponding flow-cell (FLWCL8X1C).

The Metrohm DropSens 8X110 carbon SPE (left) and the FLWCL8X1C flow-cell (right).
Instrumentation setup for the AELISS project which was launched to the ISS in October, 2020.

How did the AELISS project begin?

About five years ago, the groups from the University of Alicante and the University of Puerto Rico (UPR) began working together on microgravity experiments which led them to collaborate again for this project, which now resides on the ISS.

The electrochemical oxidation of ammonia using platinum as a catalyst is a well-established reaction, first published almost two decades ago by José’s group. The ammonia is extremely sensitive to the surface structure of platinum. However, this is well-known on earth. How does this reaction process behave in a microgravity environment? The groups sought to determine this by performing experiments in the US using a special airplane which mimics weightlessness for brief periods by flying in a parabolic motion.

SPE modification process: droplets of platinum nanoparticle ink provided by the University of Alicante deposited on the carbon SPEs. Platinum acts as a catalyst for the oxidation reaction. Click image to enlarge.

At first, this was purely for research, but later Camila’s group in Puerto Rico thought more about its potential use in space. Urea from urine is converted to ammonia, which then goes through the electrochemical oxidation process, resulting in N2 gas, water, and energy. Perhaps it was possible to use this technology to improve the onboard water recovery and recycling system in the ISS and other spaceships?

Because the UPR group often writes research proposals that are funded by NASA, they are quite knowledgeable in this area regarding the project requirements, as well as what materials are allowed on board a mission. The UPR group has been working in conjunction with NASA for about 20 years.

Unassembled equipment: plastic protector frame (grey), Metrohm DropSens FLWCL8X1C electrochemical flow-cells with 8X110 carbon SPEs (blue/white), and Nanoracks 2U (green). Click image to enlarge.

Combining the expertise in ammonia oxidation research from José’s lab in Spain with the knowledge of Camila’s group in Puerto Rico about NASA’s engineering and safety requirements made the construction and realization of the complex AELISS project possible. However, launching something to the ISS isn’t without its issues…

Has the COVID-19 pandemic had a significant effect on the research? 

Camila Morales Navas assembling the AELISS equipment in the UPR laboratory. Click image to enlarge.

Aside from the usual problems and delays that can pop up during collaborative research projects, the introduction of a global pandemic at the last stages did not help the situation. The COVID-19 pandemic affected the timeline of the AELISS project, especially when it came to traveling and working within the extremely regulated environment of NASA. Additionally, Puerto Rico had already dealt with several large earthquakes and hurricanes in this period.

Keeping each other on track became difficult at times, particularly when Camila had to bring the entire setup back home to finish the engineering. In June, she was able to return to the laboratory and complete the project. However, the stressful part was not yet over because there was still a flight to NASA in the US, and with that the ever present threat of COVID-19 infection during travel.

One positive test result would mean a denial of entry – there can be no chance of infecting the ISS crew.

Ultimately, everything went to plan before and during the launch, and the instrumentation was sent to the International Space Station in October along with other precious cargo for the astronauts. Now that this part of the puzzle is finished, the rest of the work begins…

How will AELISS differ from similar experiments on Earth?

The final goal of this research is to determine how gravity affects the oxidation of ammonia, and also to test out different catalysts for the reaction in microgravity. While several other parameters can be adjusted in the lab such as pH, nanoparticle shape, and more – gravity is a universal constraint we cannot avoid. On Earth, we are only able to mimic the effects of microgravity for a few seconds with freefall. The previous collaboration between the groups in this project also involved performing experiments on special flights that allowed weightless conditions for less than 15 seconds at a time. This is certainly not enough time to draw long-term conclusions, and hence the push to launch the project into orbit. Only then can a true comparison be made, and conclusions drawn about the effects of gravity and the future applicability of this technology.

Dr. José Solla Gullón shown in his lab at the University of Alicante depositing Pt nanocubes on the 8X110 substrates which are used in the FLWCL8X1C electrochemical cell. Click image to enlarge.

One of the major concerns regarding this project is to achieve the most efficient conversion of waste urine into usable water for long-term space missions. Here, water recycling is a critical point. Also, it is important to note that the product of the oxidation of ammonia is nitrogen gas, but the behavior of gases is not the same on Earth as in space. Understanding how the N2 bubbles behave in the absence of gravity is a critical step to study.

Camila’s doctoral research project aims to answer these questions and more, using the realistic conditions of space rather than short periods of weightlessness in flight. So how did the researchers come to use Metrohm products?

There’s Something About Metrohm

So, why choose Metrohm over other providers? I asked José and Camila just what it was that drew them to our products.

«In my case, I have been working with Metrohm DropSens for many, many years. We have a very good collaboration, not only in the in the case of the nanomaterials, but also in the electrochemical cells, and the use of the screen-printed electrodes for electroanalysis. So, we have a very long history together.»

Dr. José Solla Gullón

Distinguished Researcher at the Institute of Electrochemistry, University of Alicante

Additionally, José mentioned that it was the fact that the electrochemical cells from Metrohm DropSens were very small, perfectly fitting into their conceptual system, which was another critical point. In fact, only cosmetic changes were needed to the products to be used in this project – all of the used materials were already approved for use by NASA..

For Camila, this was her first time using these products, and she found their out-of-the-box usage incredibly helpful.

«This was my first experience since José suggested it. And I trust them because they’re the people that really know about this subject.»

Camila Morales Navas

Senior graduate student in the Department of Chemistry, University of Puerto Rico

In the past, José has asked Metrohm DropSens several times to custom design SPEs for his research needs, and has always found them responsive and agreeable.

«I know that I can send an email and in two hours, I will have some response. This is wonderful for me. They are always open to new solutions.»

Dr. José Solla Gullón

Distinguished Researcher at the Institute of Electrochemistry, University of Alicante

We wish the very best to the research groups behind the ambitious AELISS project at the University of Puerto Rico and the University of Alicante. We at Metrohm are proud that our products can contribute to space exploration.

Post written by Dr. Alyson Lanciki, Scientific Editor at Metrohm International Headquarters, Herisau, Switzerland.

Special thanks go to Dr. José Solla Gullón and Ms. Camila Morales Navas for their important research and taking time to contribute to this article.

Trace metal analysis with solid-state electrodes – Part 5

Trace metal analysis with solid-state electrodes – Part 5

by | Nov 23, 2020 | Analysis

In the last part of our series of articles about trace metal analysis using solid-state electrodes, we will have a look at the glassy carbon rotating disc electrode (GC RDE) and its application possibilities.

Did you read the other parts in this series? Find them here!
Part 1: Bismuth drop electrode
Part 2: scTRACE Gold electrode
Part 3: Modified scTRACE Gold electrode
Part 4: Screen-printed electrodes (SPEs)

The Glassy Carbon Rotating Disc Electrode

A rotating disc electrode (RDE) consists of two parts: the electrode tip which is made available in different materials, and a driving axle. The electrode tip is simply screwed onto the axle (Figure 1) to assemble the complete working electrode.

Figure 1. The two parts which make up the RDE. Left: driving axle for RDE. Right: glassy carbon electrode tip, with shaft made of glass.

Glassy carbon (GC) has a long history as solid electrode material for trace metal analysis. In general, GC is carbon with an amorphous structure which is similar to glass or ceramics, but different from graphite or diamond which both have a crystalline structure.

Aside from properties including a high temperature stability and a hardness similar to quartz, glassy carbon is very chemically inert and has a low electrical resistance, making it a versatile electrode material.

In the Metrohm GC electrode tip (Figure 1), the glassy carbon rod is fused within a glass shaft—another inert material. This design creates an electrode tip that is inert against most chemicals and solvents and guarantees measurements with excellent reproducibility due to the seamless intersection between the electrode material and glass shaft.

Modification with a metal film

For trace metal applications, the GC electrode is modified with a metal film, usually mercury or bismuth. The film is plated ex-situ from an acid plating solution which contains about 20 mg/L Hg2+ or Bi3+. Such a solution can easily be prepared from commercially available metal standard solutions and can be used for the plating of several films.

Once the film is deposited on the glassy carbon electrode, multiple determinations can be carried out with the same film. When the performance deteriorates, the exhausted film is simply wiped off and a fresh film is plated. Since only the renewable film is affected by aging processes, the GC electrode itself can be used for a very long time.

Applications using glassy carbon electrodes exhibit excellent reproducibility and stability in combination with very low detection limits.

Figure 2. Glassy carbon rotating disc electrode in a 884 Professional VA instrument from Metrohm.

Applications

Cadmium and lead determinations

The risk of cadmium and lead poisoning from drinking water and the significance of the determination of these two elements has already been discussed in previous posts in this series. To monitor the guideline values of 3 µg/L for cadmium and 10 µg/L for lead, recommended by the WHO (World Health Organization), a detection limit of β(Cd) = 0.3 µg/L and β(Pb) = 1 µg/L would be sufficient.

With the glassy carbon electrode the determination is far more sensitive, featuring a ten-fold improvement on the limit of detection of β(Cd) = 0.02 µg/L and β(Pb) = 0.05 µg/L with a deposition time of 30 s. This limit can be lowered even more with an increased deposition time.

For this extremely sensitive determination, a mercury film is plated on the glassy carbon electrode. The determination of cadmium and lead is carried out by anodic stripping voltammetry (ASV).

To learn more about this application, please check our website.

Free Application Note download: AN-V-225 Cadmium and lead in drinking water – Simultaneous determination on a mercury film modified glassy carbon electrode.

Click here to download AN-V-225

The very low detection limit makes this application especially interesting when it is not only required to monitor limit values but to actually detect concentrations in the ppt (parts per trillion, ng/L) range, e.g. in environmental analysis such as for seawater research.

Nickel and cobalt measurements

Another application with very low detection limits using the GC electrode is the determination of nickel and cobalt. This electrode allows the detection of concentrations down to β(Ni) = 0.05 µg/L and β(Co) = 0.03 µg/L. For this application, the electrode is modified with a bismuth film. The determination of nickel and cobalt is carried out by adsorptive stripping voltammetry (AdSV) using the complexing agent DMG (dimethylglyoxime).

Figure 3. Determination of β(Ni) = 0.34 µg/L and β(Co) < LOD in tap water (30 s deposition time) using the GC RDE.

For decades, this method was successfully executed with the mercury drop electrode. The use of a bismuth film on a glassy carbon electrode offers a non-toxic alternative with a similar sensitivity as the established method. Besides the high sensitivity, this application also shows excellent repeatability.

20 consecutive determinations of β(Ni) = 0.5 µg/L and β(Co) = 0.5 µg/L, carried out on the same bismuth film, showed an average recovery of 105% for nickel, with a relative standard deviation (RSD) of 2.0%. The recovery for cobalt was 112% with a RSD of 3.3%. This makes this method a viable tool in environmental analysis when natural background concentrations, which are often in the ppt (ng/L) range, should be investigated.

For further details about this application, please refer to Application Note AN-V-224: Nickel and cobalt in drinking water – Simultaneous determination in low ng/L range on the GC RDE modified with a bismuth film.

Click here to download AN-V-224

Chromium(VI) monitoring

Legal limits for chromium are relatively high. For example, the guideline value of the World Health Organization (WHO) is 50 µg/L for drinking water. These values usually refer to the total chromium concentration, but there are significant differences in toxicity between Cr(III) and Cr(VI). Even miniscule doses of Cr(VI) are toxic as well as carcinogenic.

Since the beginning of this century, there have been ongoing discussions in the scientific community about whether an additional limit value only for Cr(VI) is required, and what this value should be.

Measuring techniques are needed which allow the determination of Cr(VI) in the ng/L range. Using the glassy carbon electrode modified with a mercury film it is possible to detect Cr(VI) concentrations down to 0.05 µg/L. Cr(VI) is determined by adsorptive stripping voltammetry (AdSV) with DTPA (diethylenetriaminepentaacetic acid) as complexing agent. The recovery of a concentration of β(Cr(VI)) = 0.1 µg/L is 111% with a relative standard deviation of 4.4% (triplicate determination).

If you are interested to learn more, download our free Application Note V-277: Chromium(VI) in drinking water – Ultra-sensitive determination on the mercury film modified glassy carbon electrode (DTPA method).

Click here to download AN-V-227

All the above-mentioned applications can be carried out manually with a 884 Professional VA system (Figure 4), but it is also possible to run small sample series with an automated setup.

Figure 4. 884 Professional VA with two 800 Dosinos for automatic addition of electrolyte and standard solution.

Summary

This was the last post in our five-part series on heavy metal analysis with solid state electrodes. If this or one of the previous posts sparked your interest in one of the applications, do not hesitate to contact your local Metrohm representative.

For a complete overview of the different applications that can be performed with the SSEs exhibited in this series, check out the table below. Click on each application note or bulletin for a free download! 

Overview: Applications with Metrohm SSEs
Element Electrode Application Document Lab Portable
Ag GC RDE Application Bulletin 207

✓

✗
As scTRACE Gold Application Note V-210
Application Note V-211

✓

✓
Bi scTRACE Gold Application Note V-218

✓

✓
Cd, Pb GC RDE (Hg film) Application Note V-225

✓

✗
Cd, Pb SPE (Hg film) Application Note V-231

✓

✓
Cd, Pb Bi drop Application Note V-221

✓

✗
Cr(VI) GC RDE (Hg film) Application Note V-227

✓

✗
Cr(VI) scTRACE Gold (Hg film) Application Note V-230

✗

✓
Cu scTRACE Gold Application Note V-213

✓

✓
Fe scTRACE Gold Application Note V-216

✓

✓
Fe Bi drop Application Note V-222

✓

✗
Hg scTRACE Gold Application Note V-212

✓

✓
Ni, Co scTRACE Gold (Bi film) Application Note V-217

✓

✓
Ni, Co GC RDE (Bi film) Application Note V-224

✓

✗
Ni, Co SPE (Bi film) Application Note V-232

✓

✓
Ni, Co Bi drop Application Note V-223

✓

✗
Pb scTRACE Gold (Ag film) Application Note V-214

✓

✓
Sb(III) scTRACE Gold Application Note V-229

✓

✓
Se(IV) scTRACE Gold Application Note V-233

✓

✓
Te(IV) scTRACE Gold Application Note V-234

✓

✓
Tl scTRACE Gold (Ag film) Application Note V-228

✗

✓
Zn scTRACE Gold Application Note V-215

✓

✓

Post written by Barbara Zumbrägel, Product Manager VA/CVS at Metrohm International Headquarters, Herisau, Switzerland.

Real World Raman: Mira DS in Action – Detecting drugs safely in the field

Real World Raman: Mira DS in Action – Detecting drugs safely in the field

by | Nov 16, 2020 | Analysis

Methamphetamine (meth, Figure 1) abuse is one of the top drug problems impacting the social, economic, and health welfare of many developed and developing countries. Short-term use of meth, a powerful stimulant, provides a euphoric sense of alertness and enhanced capability for work-related activities. Chronic use inevitably leads to addiction, antisocial and sometimes violent criminal behavior, and a pronounced decline in the overall health and well-being of the user.

The proliferation and use of meth across the US, Asia, and Europe is aided by underground «kitchen» laboratories, which are the primary source of clandestine meth production and distribution.

Figure 1. Methamphetamine crystals.

Meth can be easily synthesized from pseudoephedrine extracted from over-the-counter cold medications (Figure 2) and easily purchased commercial products enriched in required reagents.

Figure 2. Pseudoephedrine tablets.

A number of different procedures have been adopted for the clandestine synthesis of meth. However, the widespread one-pot «Shake and Bake» method is uniquely adapted for covert small-scale cooking operations due to the inherent simplicity of the chemical reaction and laboratory setup.

Increasingly, methamphetamine production has moved from large-scale laboratory operations to small-scale syntheses using one-pot methods. To address this challenge, police must identify the contents of potential reaction vessels and establish a pattern of production within a discrete geographical area in order to apprehend and convict methamphetamine producers.

The target in these cases can be a discarded glass jar or plastic drink bottle containing reaction residue (Figure 3).

Figure 3. Plastic waste that appears to be the remains of a clandestine meth laboratory.

Effective suppression of meth production requires rapid confirmation of meth, or its related precursors and byproducts. Ideally, such tests are performed at the scene of suspected primitive «cooking» facilities by drug enforcement officers and first responders. On-site detection must utilize instrumentation that is compact, cost-effective, fast, and incorporates user-friendly operation procedures. 

However, rapid and portable detection capabilities for front-line law enforcement officers are lacking. These include pH strips, direct observation of odors, lab-related trash and chemical containers, and notoriously unreliable colorimetric tests. The alternative is laboratory analysis, which is complicated due to costs, time, transport, and availability.

Handheld Raman is a relatively new method that streamlines field identification of potentially flammable and explosive residues in one-pot vessels (Figure 4). Sampling and identification occurs through plastic and glass surfaces, ensuring police safety by reducing exposure to potentially hazardous materials.

Figure 4. Metrohm Raman Mira DS identifying meth in the field through a glass jar.
Did you read our last blog about handheld Raman at Metrohm? If not, read it here!
Metrohm Blog: How Mira Became Mobile

In this article, the advantage of using handheld Raman to obtain forensic evidence linking a suspected «cook» site with meth production is demonstrated. Mira DS is Metrohm’s premier handheld Raman system designed to meet the needs of first responders (Figure 5). 

Figure 5. Metrohm Raman Mira DS and optional measurement attachments for the simple identification of illicit and hazardous materials.
Want to find out more about Mira DS? Visit our website!
Identify hazardous materials at the push of a button
Safe operation with a variety of measurement attachments
Mira DS – A robust analyzer always at hand

Unlike trained analytical scientists, defense and security professionals need a solution that gives them instant results without complicated routines. With Smart Acquire, Mira DS is a point-and-shoot solution. Simply power up the instrument, touch the screen once to activate the laser and again to take a sample, then Mira DS automatically optimizes acquisition parameters, processes data, identifies the target through library matching, and delivers the results with relevant chemical warnings – all in less than a minute. When Mira DS is used with MiraCal M mobile software, these results can be shared instantly to alert others of potential danger.

 

Download our free white paper here: Smart Acquire – Automated Raman Material ID for Defense and Security Professionals.

Metrohm White Paper: Smart Acquire – Automated Raman Material ID for Defense and Security Professionals

Response Team Training with Mira DS

Simulated testing of a small-scale meth production facility was conducted in the US Midwest by the Security and Defense directorate of Metrohm USA to support Civil Support Team (CST) Training. During the Civil Support Skills CBRNE Course training, first responders are taught to recognize laboratories in which Chemical, Biological, Radiological, Nuclear or high-yield Explosive materials are being manufactured or manipulated.

Equipped with a detailed education in weapons of mass destruction and drug chemistry, attendees are required to recreate and evaluate realistic clandestine laboratories using innovative methods (Figure 6). Upon the successful completion of training, CST graduates possess unique capabilities, expertise, and an in-depth command of the technologies required for responding to CBRNE defense scenarios.

Figure 6. Images of CST test site for illicit chemical synthesis using Mira DS with Standoff Attachment for safe measurement.

During CST training, meth was synthesized using the one pot «Shake and Bake» method. This is the preferred route for making meth in low resource labs, despite relatively low product purity. The key ingredients for synthesis are easily sourced from hardware and drug stores. Preparatory procedures, the chemical reaction steps, and drug recovery can be performed in a few hours using emptied glass jars or plastic beverage bottles, tape, and tubing. Plastic is preferred to glass, as the risk of explosion during the course of the reaction is very high.

For more information about our Standoff Attachment, visit our website and watch the video below!

Testing for illicit substances is simple with Mira DS

Trainees used Mira DS (Figure 5), a handheld Raman device, to directly interrogate liquid waste in glass jars at a simulated cook site directly through the container material. Attachments for Mira DS snap on with a simple magnetic interface. Figure 7 shows the analysis of the actual one-pot meth reaction waste, seen as a bi-phasic liquid layer that remained following the removal of product. 

First, the Intelligent Universal Attachment (iUA) was used in its «bottle» setting to test each liquid waste layer directly through the glass. This attachment has three settings, including «surface» for direct contact with a material, and «bag» and «bottle» for sampling through thin and thick barriers.

Figure 7. Mira DS with Intelligent Universal Attachment in use at CST training, testing bi-phasic one-pot meth reaction waste. Left: measuring the bottom (yellow) layer – identified as calcium nitrate. Right: measuring the top (orange) layer – identified as acetone.

For more information about our Intelligent Universal Attachment (iUA), visit our website, download our free Application Note, and watch the video below!

Determination of Container Contents – Simple, Guided Method for Materials ID with Raman

Next, the Contact Ball Probe Attachment (CBP) was used to confirm the identity of the waste. CBP is a chemically resistant quick dip solution for direct sampling, and can be used with both liquids and powdered solids.

In short, Mira DS was outfitted with an attachment, powered up, the laser activated, and testing initiated using the touch screen. On-board Smart Acquire algorithms automatically optimize acquisition parameters (Laser Power, Integration Time, Averaging, etc.), process spectral data, perform library searches and matching for the user, and report results in under a minute with color-coded chemical warnings and alerts.

Results of the CST training

The library spectral stack in Figure 8 includes the product, methamphetamine, and reagents used in its synthesis during the training course. Actual data acquired during both training and real-world testing scenarios can be expected to be «messy» due to substandard reaction conditions and resulting complex chemical mixtures. Mira DS addresses this challenge by automatically correlating acquired spectra with library spectra of illicit substances, performing Mixture Matching routines, and rapidly reporting the top matches.

Figure 8. Raman Illicit Library reference spectra for the major reagents used in one-pot meth production (click to enlarge).

To learn more about identifying narcotics in complex samples using handheld Raman, download our free white paper!

Metrohm White Paper: Identifying Narcotics in Complex Samples

To summarize, Mira DS is capable of rapidly identifying key components of a popular method for clandestine meth synthesis. Two notable aspects of these results:

  • additional peaks in experimental spectra correlate with unidentified reaction byproducts, but
  • the excellent spectral resolution here, reinforced by very high correlation (HQI) scores, is a reflection of the suitability of handheld Raman as an on-site analytical tool.

In real world situations, first responders must maintain their training and stay current regarding the diverse materials and methods they are likely to encounter to ensure that Raman library entries are up to date.

Conclusion

In most situations, the product has already been removed from the cook site. Therefore one-pot meth site inspection does not realistically result in a methamphetamine identification, but the discarded waste chemicals can provide forensic evidence of meth production. These results illustrate the unique capabilities of handheld Raman in the hands of law enforcement in real world scenarios. This technique is powerful in several ways:

  • Data can be collected on-site and shared electronically for increased technical support
  • No-contact sampling of container contents reduces danger during investigation
  • Results are given in a few seconds
  • Mixture Matching provides results for real world scenarios
  • Results provide forensic evidence to link a suspected cook site with methamphetamine production

Mira DS is a promising and robust analytical tool for obtaining corroborative forensic evidence and successfully prosecuting drug crime.

Download our free white paper

Safety in Any Situation – Addressing the needs of first responders

Find it here!

Post written by Dr. Mark Harpster (Research Scientist, University of Wyoming/Applications Chemist, Metrohm Raman, Laramie, Wyoming, USA), Dr. Melissa J. Gelwicks (Applications Chemist, Metrohm Raman, Laramie, Wyoming, USA), and Dr. Bryan H. Ray (WMD Clandestine Production Laboratory Site Safety Officer Course/Civil Support Skills CBRNE Course Instructor, Metrohm USA, Tampa, Florida).

History of Metrohm IC – Part 4

History of Metrohm IC – Part 4

by | Nov 9, 2020 | Company

In the fourth installment in our series about the history of ion chromatography development at Metrohm over the years, we now focus on some of our combined analysis techniques. These are unique combinations of Metrohm instruments from different product groups which broaden application possibilities beyond what IC could accomplish alone. Here we will discuss the TitrIC and VoltIC systems.

Did you miss the other parts in this series? Find them here!

History of Metrohm IC – Part 1
History of Metrohm IC – Part 2
History of Metrohm IC – Part 3

TitrIC: combining titration, direct measurement, and IC in one

The combination of titration, pH, and conductivity measurement, as well as ion chromatography in a single analytical system was introduced in the late 1990s. This TitrIC system consisted of a Titrino for the determination of the p- and m-value (alkalinity), pH and conductivity meters, as well as a modular IC from the 732 IC Detector generation.

Figure 1. The first-generation TitrIC system from the late 1990s, including an autosampler for higher sample throughput.

Depending on the analysis requirements, either a second Titrino (for the Ca/Mg water hardness determination) or a second IC channel (for alkali and alkaline earth metal cations as well as ammonium) was selected. The latter enabled an automatic determination of the ion balance for the first time.

The central unit is the autosampler, which directs the water sample to the titration/metering section and to the ion chromatographs. The respective titration software controls the titrators and pH/temperature meters, calculates the results, and transfers them to the IC software (at the time, IC Net). The IC software controls the ion chromatograph and creates the final report. The user only communicates with the master software, making comprehensive analysis a simple task. This combination was available in all Metrohm IC generations (Figures 1 and 2). The most current setup (TitrIC Flex I and II) combines the 930 Compact IC Flex instruments with OMNIS titration.

Figure 2. TitrIC has evolved: TitrIC 7 system with 850 Professional IC series and Robotic Titrosampler has now become the TitrIC Flex (I and II), based on OMNIS titration and the 930 Compact IC Flex series.
Check out our article about the the TitrIC flex system in LCGC's The Column (11-2020)

Do you want to learn more about the combination of titration, direct measurement, and IC analysis and what it can do for your laboratory efficiency? Take a look at our previous blog post, download a free application note, or check out our brochure full of important information.

«Analyze This»: Comprehensive water analysis: combining titration, IC, and direct measurement in one setup
AN-S-387: Comprehensive water analysis with TitrIC flex II
TitrIC flex – All you need for comprehensive water analysis

VoltIC – Voltammetry and IC

Just as with titration, it also is possible to combine IC and voltammetry in order to further expand application capabilities for enhanced trace measurement of analytes in water. VoltIC Professional integrates these techniques in a single, fully automatic system that is controlled via a common software, providing users with the strengths of both IC and voltammetry. Anions, major cations as well as trace cations may be detected in one determination. 

Back in 2012, the original VoltIC pro system was launched to bridge the gap between these two techniques and to offer a unique solution to the market. In 2013, the new line of 940 Professional IC Vario instruments came along. A few years later in 2016, the 884 Professional VA analyzer was brought to the market, and thus VoltIC on the next level: the current VoltIC Professional system (Figure 3).

Figure 3. VoltIC Professional system developed in 2016 for the enhanced analysis of trace impurities in water samples.

Is VoltIC the right choice for your laboratory? We offer free application notes for download, or check out the Metrohm website and download our brochure!

Free application notes for the VoltIC Professional system
Visit the VoltIC webpage here!
Download the VoltIC brochure

Next topic:

In Part 5 of our series, we describe the use of ion chromatography for continuous air monitoring with the MARGA from Metrohm Process Analytics.

History of Metrohm IC – Part 5

Download our free monograph:

Practical Ion Chromatography – An Introduction

Click here!

Post written by Dr. Markus Läubli, Manager Marketing Support IC at Metrohm International Headquarters, Herisau, Switzerland.

Frequently asked questions in near-infrared spectroscopy analysis – Part 2

Frequently asked questions in near-infrared spectroscopy analysis – Part 2

by | Nov 2, 2020 | Analysis, Evaluating results, Sampling

Whether you are new to the technique, a seasoned veteran, or merely just curious about near-infrared spectroscopy (NIRS), Metrohm is here to help you to learn all about how to perform the best analysis possible with your instruments.

In this series, we will cover several frequently asked questions regarding both our laboratory NIRS instruments as well as our line of Process Analysis NIRS products.

Did you miss Part 1 in this series? Find it here!

NIRS FAQ – Part 1

The following topics will be covered in the rest of this post (click to jump to the topic):

  1. What are typical detection limits for liquid samples and for solid samples?
  2. What accuracy can I achieve with NIR spectroscopy?
  3. How are instruments calibrated and how often do I need to recalibrate an instrument?
  4. How do I validate my instrument and how frequently should validation be done?
  5. What sample types or parameters are not suitable for analysis with NIR spectroscopy?
  6. My industrial process is full of harsh chemicals, so manual sampling is not desirable. Is it possible to perform inline NIR analysis in hazardous areas?
  7. How is the maintenance of a NIR process analyzer performed?

1. What are typical detection limits for liquid samples and for solid samples?

The detection limit varies depending on the substance analyzed, the complexity of the sample matrix, and the sensitivity of both the reference and NIR technology used. NIR spectroscopy systems using dispersive technology are the most sensitive. Using such a system to analyze a simple sample in which the parameter of interest is a strong absorber will allow low detection limits.

For example, water in solvents can be detected down to about 10 mg/L in both offline and online/inline measurements. For more complex matrices (e.g., solids and slurries), detection limits are about 1000 mg/L (0.1%).

For more information about the differences between solid and liquid samples for NIRS analysis, as well as the different methods best suited for such matrices, read our blog post «Benefits of NIR spectroscopy: Part 1» here!

«Analyze This»: Benefits of NIR spectroscopy: Part 1

2. What accuracy can I achieve with NIR spectroscopy?

The accuracy of a near-infrared spectroscopic method depends on the accuracy of the reference/primary method. A highly accurate primary method will result in the development of a highly accurate NIR method, while a less accurate primary method lowers the accuracy of the related NIR method. This is because the NIR data and primary data are correlated in the prediction model. A good prediction model will have approximately 1.1x the accuracy of the primary method over the prediction range.

The development of prediction models has been described in detail in our previous blog article: «Benefits of NIR spectroscopy: Part 3».

«Analyze This»: Benefits of NIR spectroscopy: Part 3

3. How are instruments calibrated and how often do I need to recalibrate an instrument?

Instruments are calibrated using certified NIST standards. For dispersive systems measuring in reflection mode, NIST SRM 1920 standards are used to calibrate the wavelength / wavenumber axis. Certified reflection standards with a defined reflectance made of ceramic can be used to calibrate the absorbance axis.

In transmission mode, typically NIST SRM 2065 or 2035 are used for the wavelength / wavenumber calibration, and air for the absorbance axis.

A calibration should be performed after each hardware modification (e.g., lamp exchange) and annually as part of a service interval. Ideally, the spectroscopy software guides user through the complete calibration processes.

Find the calibration tools for your Metrohm NIRS instruments here!

Calibration tools for Metrohm NIRS instruments
Metrohm NIRS reflection standard, set of 2.

4. How do I validate my instrument and how frequently should validation be done?

The Metrohm NIRS DS2500 Solid Analyzer.

NIR spectroscopy software offers different tests to validate the performance of the instrument. The most common one is a basic performance test, which tests some crucial hardware parts as well as the wavelength/wavenumber calibration and the signal to noise (S/N) of the system.

For the regulated environment, further tests according to the USP <856> guidelines are typically implemented, including photometric linearity and noise at high and low light fluxes. Instrument performance tests should be performed on a regular basis, with the frequency depending on risk assessment.

5. What sample types or parameters are not suitable for analysis with NIR spectroscopy?

Samples containing a high amount of carbon black cannot be analyzed by NIR spectroscopy because carbon black absorbs almost all NIR light.

Further, most inorganic substances have no absorbance bands in the NIR spectral region and are therefore not suitable for NIR analysis.

Find out more about the molecules and functional groups which are active in the NIR region of the electromagnetic spectrum in our previous blog post: «Benefits of NIR spectroscopy: Part 2».

«Analyze This»: Benefits of NIR spectroscopy: Part 2
Carbon black is not a suitable sample to be measured by NIR technology.

Are you looking for more spectroscopy applications? Check out the Metrohm Application Finder to download free applications across a variety of industries!

Metrohm Application Finder: free spectroscopy applications

6. My industrial process is full of harsh chemicals, so manual sampling is not desirable. Is it possible to perform inline NIR analysis in hazardous areas?

Yes, and we have the right solutions for you. Metrohm not only manufactures instruments for laboratory analysis, but we also cater to the industrial process world! Metrohm Process Analytics offers two versions of process NIRS systems: the NIRS Analyzer Pro and the NIRS XDS Process Analyzer, the latter being the ideal solution for hazardous environments.

Metrohm Process Analytics offers two lines of near-infrared spectroscopic process analyzers: the NIRS Analyzer PRO and the NIRS XDS Process Analyzer.

NIRS is a robust and extremely versatile method, which enables simultaneous, «real-time» monitoring of diverse process parameters with a single measurement. The use of fiber-optics in NIRS means that the process analyzer and measuring point can be spatially separated – even by hundreds of meters if required. In fact, remote monitoring can be achieved at large distances without significant impact to S/N ratios. This is a huge advantage in environments with challenging explosion protection requirements. Fiber-optic probes and flow cells can be placed in very harmful working environments, while the spectrometer and analysis PC remain safe and secure in a shelter. When a shelter is not available, the NIRS XDS Process Analyzer can be directly placed in the hazardous area (ATEX Zone 2 or Class1Div2).

Obtain «real-time» results of your process without the need to take samples, reduce the risks of handling chemicals, and increase your profitability. Download our free brochure here for more information about safe operation of NIRS process analyzers in hazardous areas!

NIRS Explosion Proof Analyzers – Safe operation in hazardous areas: good practice with Metrohm Process Analytics expertise

7. How is the maintenance of a NIRS process analyzer performed?

Maintenance is easy, fast, and not necessary to perform very often. NIRS is a reagentless analytical technique, so the only consumable to be replaced is the lamp, which needs replacement once per year.

Compared to other techniques like chromatography  (e.g., GC, IC) or titration, and also because NIR spectroscopic analysis does not degrade samples, there is no chemical waste which is produced. Additionally, thanks to our all-in-one software, automatic performance tests are performed regularly to guarantee that the analyzer is operating according to process specifications. The instrument can be left in the process without any further operator involvement. 

Metrohm Process Analytics NIRS process analyzers are maintenance-free systems that have been designed to guarantee high uptimes and low operational costs.

Are you searching for more process NIRS applications? Check out the Metrohm Application Finder to download them for free!

Free Metrohm Application Notes: NIRS used in process analysis

Want to learn more about NIR spectroscopy and potential applications? Have a look at our free and comprehensive application booklet about NIR spectroscopy.

NIR spectroscopy: The efficiency boost for QC labs

Download our Monograph

A guide to near-infrared spectroscopic analysis of industrial manufacturing processes

Click here to learn more!

Post written by Dr. Nicolas Rühl (Product Manager Spectroscopy at Metrohm International Headquarters, Herisau, Switzerland) and Dr. Alexandre Olive (Product Manager Process Spectroscopy at Metrohm Applikon, Schiedam, The Netherlands).

Thermometric titration – the missing piece of the puzzle

Thermometric titration – the missing piece of the puzzle

by | Oct 26, 2020 | Analysis, Evaluating results, Fundamentals

Titration is a well-established analysis technique taught to each and every chemistry student. Titration is carried out in nearly every analytical laboratory either as manual titration, photometric titration, or potentiometric titration. In this blog entry, I would like to present an additional kind of titration you may  not have heard of before – thermometric titration – which can be considered the missing piece of the titration puzzle.

Here, I plan to cover the following topics:
  1. What is thermometric titration?
  2. Why consider thermometric titration?
  3. Practical application examples

What is thermometric titration?

At first glance, thermometric titration (TET) looks like a normal titration and you won’t see much (or any) difference from a short distance. The differences compared to potentiometric titration are in the details.

TET is based on the principle of enthalpy change (ΔH). Each chemical reaction is associated with a change in enthalpy which in turn causes a temperature change. During a titration, analyte and titrant react either exothermically (increase in temperature) or endothermically (decrease in temperature).

During a thermometric titration, the titrant is added at a constant rate and the change in temperature caused by the reaction between analyte and titrant is measured. By plotting the temperature versus the added titrant volume, the endpoint can be determined by a break within the titration curve. Figure 1 shows idealized thermometric titration curves for both exothermic and endothermic situations.

Figure 1. Illustration of exothermic and endothermic titration curves showing clear endpoints where the temperature of the solution changes abruptly.

What happens during a thermometric titration?

During an exothermic titration reaction, the temperature increases with the titrant addition as long as analyte is still present. When all analyte is consumed, the temperature decreases again as the solution equilibrates with the atmospheric temperature and/or due to the dilution of the solution with titrant (Figure 1, left graph). This temperature decrease results in an exothermic endpoint.

On the contrary, for an endothermic titration reaction, the temperature decreases with the titrant addition as long as analyte is still available. When all analyte is consumed, the temperature stabilizes or increases again as the solution equilibrates with the atmospheric temperature and/or due to the dilution of the solution with titrant (Figure 1, right graph). This temperature decrease results in an endothermic endpoint.

Knowing the absolute temperature, isolating the titration vessel, or thermostating the titration vessel is thus not required for the titration.

Figure 2. Metrohm’s maintenance-free Thermoprobe used for the reliable indication of thermometric endpoints.

In order to measure the small temperature changes during the titration, a very fast responding thermistor with a high resolution is required. These sensors are capable of measuring temperature differences of less than 0.001 °C, and allow the collection of a measuring point every 0.3 seconds (Figure 2). 

Visit the Metrohm website to learn more about the fast, sensitive Thermoprobe products available even for aggressive sample solutions.

Metrohm Thermoprobe

If you would like to learn more about the theory behind TET, then download our free comprehensive monograph on thermometric titration.

Monograph: Practical thermometric titrimetry

Why consider thermometric titration?

Potentiometric and photometric titration are already well established as instrumental titration techniques, so why should one consider thermometric titration instead?

 

TET has the same advantages as any instrumental titration technique:
  • Inexpensive analyses: Titration instruments are inexpensive to purchase and do not have high running and maintenance costs compared to other instruments for elemental analysis (e.g., HPLC or ICP-MS).
  • Absolute method: Titration is an absolute method, meaning it is not necessary to frequently calibrate the system.
  • Versatile use: Titration is a universal method, which can be used to determine many different analytes in various industries.
  • Easy to automate: Titration can be easily automated, increasing reproducibility and efficiency in your lab.
«Analyze This»: Why consider automation – even for simple titrations
In comparison to classical instrumental titration, thermometric titration has several additional advantages:
  • Fast titrations: Due to the constant titrant addition, thermometric titrations are very fast. Typically, a thermometric titration takes 2–3 minutes.
  • Single sensor: Regardless of the titration reaction (e.g., acid-base, redox, precipitation, …), the same sensor (Thermoprobe) can be used for all of them.
  • Maintenance-free sensor: Additionally, the Thermoprobe is maintenance free. It requires no calibration or electrolyte filling and can simply be stored dry.
  • Less solvent: Typically, thermometric titrations use 30 mL of solvent or even less. The small amount of solvent ensures that the dilution is minimized, and the enthalpy changes can be detected reliably. As a side benefit, less waste is produced.
  • Additional titrations possible: Because enthalpy change is universal for any chemical reaction, thermometric titration is not bound to finding a suitable color indicator or indication electrode. This allows the possibility of additional titrations which cannot be covered by other kinds of titration.
  • Easier sample preparation: As TET uses higher titrant concentrations it is possible to use larger sample sizes, reducing weighing and dilution errors. Tedious sample preparation steps such as filtration can be omitted as well.
Figure 3. The Metrohm 859 Titrotherm with 801 Stirrer and notebook with tiamo™ software.

Learn more about the 859 Titrotherm system for the most reliable TET determinations on the Metrohm website.

859 Titrotherm complete with tiamo™ software

Practical application examples

In this section I would like to present you some practical examples where TET can be applied.

Acid number and base number

The acid number (AN) and base number (BN) are two key parameters in the petroleum industry. They are determined by a nonaqueous acid-base titration using KOH or HClO4, respectively, as titrant.

During such determinations, very weak acids (for AN analysis) and bases (for BN analysis) are titrated with only small enthalpy changes. Using a catalytic indicator, these weak acids and bases can also be determined by TET.

ASTM D8045 describes the analysis of the AN by thermometric titration. The benefits of carrying out this titration are:

  • Less solvent (30 mL instead of 60 or 120 mL), meaning less waste
  • Fast titration (1–3 minutes)
  • No conditioning of the sensor

If you wish to learn more about how well the results of the AN determination according to ASTM D8045 correlate with ASTM D664, download our free White Paper WP-012 as well as our brochure below.

White Paper WP-012: Avoid corrosion—A new method for TAN determination in crude oil and petroleum products
Determination of AN in crude oil and in petroleum products in accordance with ASTM D8045 – Precise and reproducible results in 60 seconds

For more detailed information about the titration itself, download the free Application Bulletin AB-427 (AN) and Application Bulletin AB-405 (BN) below.

AB-427: Acid number in raw oils and petroleum products through thermometric titration in accordance with ASTM D8045
AB-405: Determination of the total base number in petroleum products

Sodium

Using conventional titration, the salt content in foodstuff is usually determined based solely on the chloride content. However, foods usually contain additional sources of sodium, e.g. monosodium glutamate (also known as «MSG»). With TET it becomes possible to titrate the sodium directly, and thus to inexpensively determine the true sodium content in foodstuff, as stipulated in several countries.

If you wish to learn more about the sodium determination, watch our Metrohm LabCast video: «Sodium determination in food: Fast and direct thanks to thermometric titration».

For more detailed information on the titration itself, download the free Application Bulletin AB-298 here.

AB-298: Automated sodium determination in various foods with 859 Titrotherm

Fertilizer analysis

Fertilizers consists of various nutrients, including phosphorus, nitrogen, and potassium, which are important for plant growth. TET enables the analysis of these nutrients by employing classical gravimetric reactions as the basis for the titration (e.g., precipitation of sulfate with barium). This allows for a rapid determination, without needing to wait hours for a result, as with conventional procedures based on drying and weighing the precipitate.

Nutrients which can be analyzed by TET include:
  • Phosphate
  • Potassium
  • Ammoniacal nitrogen
  • Urea nitrogen
  • Sulfate

Want to learn more about the analysis of fertilizers with thermometric titration? Download our free White Paper WP-060 on this topic. For more detailed information regarding the different fertilizer applications, check out the Metrohm Application Finder, or find a curated selection here.

WP-060: Multiparameter analysis in fertilizers – Fast and easy via thermometric titration
Metrohm Application Finder: TET applications for fertilizers
Quality control of NPK fertilizers – Rapid and reliable analysis by thermometric titration

Metal-organic compounds

Metal-organic compounds, such as Grignard reagents or butyl lithium compounds, are used for synthetizing active pharmaceutical ingredients (APIs) or manufacturing polymers such as polybutadiene. With TET, the analysis of these sensitive species can be performed rapidly and reliably by titrating them under inert gas with 2-butanol.

If you wish to learn more about this topic, check out our news article and download the free corresponding Application Note AN-H-142.

Thermometric titration – fast and highly accurate determination of metal organic compounds
AN-H-142: Determination of metal-organic compounds

These were just a few examples about the possibilities of thermometric titration, to demonstrate its versatile use. For a more detailed selection, have a look at our Application Finder.

Download free TET applications from Metrohm here!

To summarize:

  • TET is an alternative titration method based on enthalpy change
  • A fast and sensitive Thermoprobe is used to determine exothermic and endothermic endpoints
  • Thermometric titration is a fast analysis technique providing results in less than 3 minutes
  • Thermometric titration can be used for various analyses, including titrations which cannot be performed otherwise (e.g., sodium determination)

I hope this overview has given you a better idea about thermometric titration – the missing piece of the titration puzzle.

For more information

Download our free Monograph:

Practical thermometric titrimetry

Click here!

Post written by Lucia Meier, Technical Editor at Metrohm International Headquarters, Herisau, Switzerland.