«Analyze This»: 2020 in review

by Alyson Lanciki | 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 60^th 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
Titration
Karl Fischer Titration
Ion Chromatography (IC)
Near-Infrared Spectroscopy (NIRS)
Raman Spectroscopy

Process Analytics
Voltammetry (VA)
Electrochemistry (EC)
The History of…
Specialty Topics
Industry-focused

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.

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.

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.

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.

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

by Alyson Lanciki | 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).

Combat food fraud: Meet Misa

by Alyson Lanciki | Jun 29, 2020 | Analysis

What’s on your plate?

Food fraud is an ever-present danger around the world. Despite increased regulations, huge scandals still occur regularly, such as deliberately tainted infant formula (2008), or the horse meat affair in the UK due to improper labelling (2013). Other more common examples include the adulteration of highly valued items with lower cost substitutes, or the illegal enhancement of color in foods and beverages with unsafe dyes.

As the population continues to increase, driving the demand for high quality food and beverage choices, so will the amount of food fraud cases. Only a concerted effort to test foodstuffs more frequently in an efficient manner along the supply chain with accurate and precise analytical techniques will bring these cases to light before more people come to harm.

Misa to the rescue

Meet the newest addition to the Metrohm Instant Raman Analyzer family: Misa, the Metrohm Instant SERS Analyzer. Misa is fast, smart, and portable with powerful algorithms that simplify high-tech analyses for non-technicians. Misa is designed with safety in mind, purposefully designed to detect illicit drugs and food additives in complex matrices.

The SERS Principle

Surface Enhanced Raman Scattering (SERS) is an extension of Raman. Perhaps you read in my previous blog post about Raman spectroscopy that «If you can see it, Raman can ID it»… well, SERS amplifies the Raman signal of trace analytes, making it an extremely sensitive method for «ID when you can’t see it.»

Metrohm Blog: How Mira Became Mobile

When SERS-active analytes adsorb to silver or gold nanoparticles, their Raman signal is enhanced as much as a million-fold, providing incredibly sensitive detection abilities.

SERS is used in biosensor applications, including single-cell sensing, antibody detection, and pathogen monitoring. It can be used to detect chemical warfare agents and illicit drug laboratory residues. Additionally, SERS is a particularly powerful technique for detecting trace contaminants in foodstuffs such as antibiotics fungicides, pesticides, herbicides, illicit dyes, and other additives.

Free White Paper: Surface Enhanced Raman Scattering (SERS) – Expanding the Limits of Conventional Raman Analysis

If you know ID Kit for Mira DS, then you already know a little about SERS. SERS is an «enhancement» technique to Raman that enables detection of trace materials. For example, ID Kit was developed as a method for identifying heroin and fentanyl in street drug samples. The cutting agents and added stimulants that constitute the bulk of street heroin fluoresce under investigation with Raman and overwhelm the signal coming from heroin. SERS sees right through the cutting agents and identifies the drug.

Free White Paper: Determination of Heroin in Street Drug Samples

Overlaid Raman and SERS spectra demonstrating the ability of SERS to detect the active ingredient in street heroin.

Another example of how Raman and SERS complement each other can be seen with Yaba, a common street drug in southeast Asia. Yaba is a red tablet that contains significant caffeine with a small amount of methamphetamine. When a red Yaba tablet is analyzed with Raman, caffeine and the red dye in the coating are the primary identification targets. This makes sense, because Raman is very good at identifying bulk materials.

However, when a Yaba tablet is subjected to SERS analysis, the story is very different (reminder: these are both also capabilities of Mira DS!) Only SERS can ID the methamphetamine in Yaba and complete the story.

Protecting Consumer Safety with Misa

Consumer safety relies on the ability of food inspectors to detect unwanted additives and assure the quality of the products. Trace detection of food adulterants is traditionally very involved laboratory work, using HPLC, GC/MS, and other techniques requiring extensive sample preparation and scientific training. Misa is designed to simplify food testing, from sample preparation, to sharing results.

The unique capabilities of Misa and SERS analysis in food testing deserve some explanation. Raman is used in food testing in some incredible ways: identifying counterfeit honey, distinguishing scotch from different producers, discriminating between very similar sugars, even making a distinction between grass- and grain-fed beef. However, these are bulk, inherent qualities of a food.

Looking for trace levels of pesticides is a very different science. A successful SERS analyte must interact with nanoparticles—target molecules with amine, carboxyl, and thiol groups often have the required interaction. Fortunately, many food additives fit this definition. Metrohm Raman sponsored a year-long study to identify 82 different food adulterants that can be successfully detected with our SERS substrates. That was just the beginning.

Are you looking for applications suitable for Misa? Check out our free selection of application notes available on the Metrohm website:

Misa Application Notes

Additionally, reference spectra for several other analytes can be obtained by contacting your local Metrohm sales organization.

The next step was to determine the foods which were typically treated with these illicit substances, then how to simplify sample preparation for potentially demanding food matrices. Metrohm Raman is taking two different approaches to this challenge. First, Misa will be released with 17 different «real world» food safety applications (click to download):


Aspartame in Diet Soda	Melamine in Dairy Products
Auramine O in Curry Powder	Metanil Yellow in Turmeric
Brilliant Blue in Foodstuffs	Paraquat in Tea Leaves
Carbendazim on Strawberries	Potassium Ferrocyanide in Table Salt
Diphenylamine in Baby Food	Pyrimethanil in Wine
Erthyrosine B in Sugar	Rhodamine B in Cayenne
Fenthion in Olive Oil	Thiabendazole on Bananas
Malachite Green in Aquaculture Media	Thiram on Apples
Malathion on Corn	…and more to come

Misa is a unique instrument, which is reflected in this broad collection of Application Notes (AN). In addition to standard spectra and experiments, each AN includes a special section titled «Field Test Protocol». Briefly, the Field Test Protocol guides any user through a complete experiment using Misa and the tools in the ID Kits. ID Kits for Misa contain dedicated SERS substrates, in addition to the basic tools required for field testing. These, combined with companion Operating Procedures included on Misa, make food safety testing accessible to anyone, anywhere.

Our second approach to application development for Misa is a very interactive process with our users as we identify the target and food matrix, provide standard spectra for library building, advise sample preparation, and help to optimize results. This approach acknowledges that food is different around the world, adulterants vary, and concerns may be localized. These ANs that accompany Misa at release are intended to give the user an idea of how to use SERS and when it is a useful technique for detection of food contaminants, but custom applications will certainly increase demand for Misa.

Metrohm Raman is excited to introduce you to Misa. Misa has all of the qualities that you appreciate about Mira—intuitive user interface, simple guided workflow, and smart attachments to facilitate onsite testing by non-chemists. Our approach to simplifying food testing includes libraries, dozens of reference spectra, and developed applications targeting food adulterants.

Visit our website

and discover more about how Misa can help the fight against food adulteration scandals.

Click here!

Post written by Dr. Melissa Gelwicks, Technical Writer at Metrohm Raman, Laramie, Wyoming (USA).

How Mira Became Mobile

by Alyson Lanciki | Mar 9, 2020 | Analysis, Company, Fundamentals, Sampling

Handheld Raman spectrometers are truly like no other analytical chemical instruments. All spectrometers (e.g. IR/NIR, UV-Vis, GC/MS, and Raman) rely on interactions between matter and energy and include detectors that collect information about resulting atomic and molecular changes. This information is used to qualify and/or quantify various chemical species. Typically, a spectrometer is a benchtop instrument attached to a computer or other visual display that is used by an analytical chemist in a laboratory.

Classical Raman spectrometers fall into this category. Lasers, filters, detectors, and all associated hardware for sampling is combined in one unit, while data processing and viewing occurs nearby.

For a comparison of other spectroscopic techniques, visit our previous blog post «Infrared spectroscopy and near infrared spectroscopy – is there a difference?».

Raman is a unique investigative analytical technique in many ways. It is said, «If you can see it, Raman can ID it.»

Indeed, Raman’s strengths are its simple sampling methods combined with its specificity. Direct analysis is possible for many pure substances without sample preparation. Sampling is performed via direct contact with a substance, remotely, or through a barrier. Even solutes in water may be directly identified. This technique is highly specific; each material investigated with Raman produces a unique «fingerprint» spectrum. Raman spectroscopy is successful at positively identifying each distinct substance, while accurately rejecting even very similar compounds.

Mira (Metrohm Instant Raman Analyzer) with several sampling attachments for easy analysis: with or without sample contact.

The Raman spectrum

Raman spectra contain peaks across a range that correspond to specific molecular connectivity and can be used to determine the composition of a sample. The spectral range is dependent on spectrometer design, and embodies a balance of resolution and sensitivity.

The «fingerprint region» (400–1800 cm^-1) is used to ID unknowns and verify known materials. The region below 400 cm^-1 is helpful in the analysis of minerals, gemstones, metals, and semiconductors. For most organic materials (oils, polymers, plastics, proteins, sugars/starches, alcohols, solvents, etc…), very little information above 2255 cm^-1 is useful in Raman applications, as carbon-hydrogen chains contribute little to molecular qualification.

A selection of different bonds and functional groups with their general regions of activity in the Raman portion of the electromagnetic spectrum (click to enlarge).

Mira’s measuring range of 400–2300 cm^-1 is perfect for most Raman applications, including:

Pharma & Other Regulated Industries
Food
Personal Care & Cosmetics
Defense & Security
Process Analytics
Materials ID
Education & Research

Mira is available in different configurations for all kinds of applications and user needs.

Find out more about Mira P here

Click here to learn about Mira DS

Good things come in small packages

Technology, analysis, ease of use, accuracy—handheld Raman has all of this in a small format that escapes the confines of the lab. It also invites many new types of users who employ Raman for vastly new and exciting applications. In the rest of this blog post, I share details about the development of components that led to miniaturization of Raman. This is followed by the origin story of Metrohm Raman, manufacturer of Mira (Metrohm Instant Raman Analyzers).

Four significant innovations came together to create Mira: diode lasers, specialized filters and gratings, on-axis optics, and the CCD (Charge Coupled Device) in a unique design called the «astigmatic spectrograph». These basic components of a Raman spectrograph can be seen in the graphical representation above (click to enlarge). Note that this is not an accurate depiction of the unique geometries found within Mira’s case!

Raman spectroscopy is a technique which relies on the excitation of molecules with light (energy). C.V. Raman’s discovery of Raman scattering in 1928 was enabled by focused sunlight, which was then quickly replaced with a mercury lamp for excitation and photographic plates for detection. This resulted in a simple, popular, and effective method to determine the structure of simple molecules.

C.V. Raman. India Post, Government of India / GODL-India

The first commercial Raman spectrometer was available in the 1950’s. As lasers became more available in the 1960’s, followed by improved filter technology in the 1970’s, Raman grew in popularity as a technique for a wide range of chemical analysis. Integrated systems were first seen in the 1990’s, and the miniaturization of instruments began in the early 2000’s.

Miniaturization of Raman spectrometers

Diode lasers were the first step toward handheld Raman. For those of you at a certain age, you may remember that these are the kind of small, cool, low energy lasers used in CD players, stabilized at the source with a unique kind of diffraction grating.

Powerful, efficient optical filters also contribute to miniaturization by controlling laser light scattering within the spectrograph. The development of sensitive, small Charge Coupled Devices (CCDs), which are commonly used in mobile phone cameras, permitted the detection of Raman scattering and efficient transmission of the resulting signals to a computer for processing.

The astigmatic spectrograph simplified both geometry and alignment for the many components within a Raman spectrometer; this design was the final advancement in the development of handheld Raman.

From Wyoming to Switzerland

By the 1990’s, new technologies developed for diverse industries were being incorporated into Raman spectroscopy. In Laramie, WY (USA) at the time, Dr. Keith Carron was a professor of Analytical Chemistry with a focus on Surface Enhanced Raman Scattering (SERS). Dr. Carron already had robust SERS tests, but he envisioned a low-cost Raman system that would introduce his tests to industrial, medical, or defense and security markets. His next steps would revolutionize Raman spectroscopy.

Using commercial off-the-shelf parts, Dr. Carron and his team developed an economical benchtop instrument that eliminated the high cost of Raman analysis, helping to enable its use in university curricula. In the early 2000’s, a research and education boom began as Raman grew from an esoteric technique used in high-end applications to becoming widely available for all kinds of tasks. Dr. Carron is responsible for ushering Raman into the current era. A collaboration led to a portable Raman system and, ultimately, to a new astigmatic spectrograph design in a very small instrument.

The U.S. tragedies on September 11, 2001 created an immediate push for technology to detect terrorist activity. Around this time, anthrax scares further enforced the need for “white powder” analyzers. Fieldable chemical analysis became the goal to achieve.

Dr. Carron was inspired to invent a truly handheld, battery powered Raman device for the identification of explosives and other illicit materials. A number of iterations led to CBex, a palm-sized Raman system (even smaller than Mira!) designed by Snowy Range Industries, in February 2012 (see image). CBex caught the attention of Metrohm AG, and an offer of cooperation was sent to Dr. Carron in August 2013.

Along comes Mira

Mira was born in 2015. Not only is it a novel analytical instrument, but it is also unique amongst handheld Raman spectrometers. Mira has the smallest form factor of all commercially available Raman instruments. What truly sets Mira apart from the competition is its built-in Smart Acquire routines, which provide anyone, anywhere, access to highly accurate analytical results. It is rugged, meeting MIL-STD 810G and IP67 specifications—you can drop Mira or submerge it in a liquid to get an ID.

Once Raman escaped the confines of the laboratory, it suddenly had the potential for new uses by non-technical operators, who could perform highly analytical tests safely, quickly, and accurately.

In fact, miniaturization of Raman has revolutionized safety in a number of ways:

Direct analysis eliminates dangers from exposure to laboratory solvents and other chemicals.
Through-packaging analysis prevents user contact with potentially hazardous materials.
Simplified on-site materials ID verifies the quality of ingredients in foods, medicines, supplements, cosmetics, and skin care products.
ID of illicit materials such as narcotics, explosives, and chemical warfare agents supports quick action by military and civilian agencies.

What’s Next?

I hope that you have enjoyed learning about the evolution of Raman technology from benchtop systems to the handheld instruments we have today. In the future, we will publish more articles about Mira that describe, in detail, several interesting applications of handheld Raman spectroscopy.

You can find the first one of these articles below!