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The Eastern Analytical Symposium (EAS) Award for Outstanding Achievements in Mass Spectrometry will be presented to Barbara Larsen on Thursday, November 19.

is a Nutrition and Biosciences fellow at the DuPont Experimental Station in Wilmington, Delaware. Her research focuses on the application of mass spectrometry to support the biotechnology business. She has a keen interest in ionization methods to ensure the continued relevance of mass spectrometry for biotechnology projects at DuPont. Larsen has a passion for 

—selecting the best measurement technology to provide the critical solution to a specific problem. For her work supporting biotechnology research, Larsen has developed a digestion protocol for bioproteins that provides coverage of the expressed protein sequence or deep proteomic coverage of the organism that produced the protein. In addition, these methods can be used to provide details on protein modifications that occur during host expression or during processing. Her research interests include using a systems biology approach including metabolomics, proteomics, and transcriptomics to improve enzyme production and probiotic organisms.

Larsen has been part of the DuPont Company for the past 35 years. She received her BS from the University of Santa Clara, California, and her PhD in Physical Chemistry at the University of Delaware, followed by a post-doctoral fellowship at Johns Hopkins School of Medicine. Larsen has received the Spectroscopy Society Award and the Delaware ACS Section Research Award. DuPont awarded her research with the Pederson Award, for significant scientific achievement that reflects technical excellence. 

She is currently a member of American Society of Mass Spectrometry—where she has served as the treasurer, vice president of programs, and president—and is on the advisory board for the society journal. As an active member of the American Chemical Society (ACS), she was made an ACS fellow for her service as the chair for the Delaware Valley Mass Spectrometry Discussion Group and as a counselor for the Delaware ACS section. She also serves on the editorial advisory board of 

Articles

Barbara Larsen Receives EAS Award for Outstanding Achievements in Mass Spectrometry

The New York Society for Applied Spectroscopy Gold Medal Award will be presented to Jerome Workman, Jr. and Howard Mark at the Eastern Analytical Symposium (EAS) on Wednesday, November 18. Workman is scheduled to deliver a talk on “The Present and Future of Chemometrics in the Analytical Sciences” while Mark is scheduled to deliver a talk on the “History of Calibration Transfer.” This year marks only the second time the committee has selected two winners for the Gold Medal Award since its inception in 1952. Mark and Workman were recognized for their contributions, individually and as a team, to the field of near-infrared (NIR) spectroscopy and chemometrics, leading to a wider adoption of the technology in the spectroscopy community.

Jerome Workman, Jr. is currently the Senior Technical Editor for 

. He is also a Certified Core Adjunct Professor at National University in San Diego, California, and a principal at Biotechnology Business Associates. He was formerly the Executive Vice President of Research and Engineering for Unity Scientific and Process Sensors Corporation. Workman has more than 75 U.S. and international patent applications since 1998 with 25 issued U.S. and international patents and multiple trade secrets. He has more than 500 technical publications, including 22 reference books on a broad range of spectroscopy, chemometrics, and data processing topics.he also has received many awards, including the 2002 Eastern Analytical Symposium Award for Achievements in NIR, the 2002 ASTM International Award of Merit, the 2009 Coblentz Society Williams-Wright Award, as well as awards from the Society for Applied Spectroscopy, National Institute of Standards and Technology (NIST), Frost and Sullivan, and other organizations. He is a fellow of the American Institute of Chemists, ASTM International, and the Royal Society of Chemistry.

Howard Mark serves on the Editorial Advisory Board of 

and runs a consulting service, Mark Electronics, in Suffern, New York. Mark has authored 243 papers including 75 installments of the "Statistics in Spectroscopy" column and 123 installments of "Chemometrics in Spectroscopy," four books, numerous book chapters, and seven patents. He was a Student Awardee to the 1964 Eastern Analytical Symposium, and has received the 2003 Eastern Analytical Symposium award for Outstanding Contributions in the Field of Near Infrared Spectroscopy, an Honorary Life Membership to the Council for Near Infrared Spectroscopy, awarded in 2010, and the 2011 Coblentz Society's Williams-Wright award for Outstanding Contributions to the Field of Industrial Vibrational Spectroscopy. Mark’s interests focus on application of electronics and especially, computers, to chemical Instrumentation and analysis, with emphasis on gas chromatography and spectroscopy, particularly mid- and near-infrared spectroscopy.

The New York Society for Applied Spectroscopy Gold Medal Award will be presented to Jerome Workman, Jr. and Howard Mark at the Eastern Analytical Symposium (EAS) on Wednesday, November 18.

Jerome Workman, Jr. and Howard Mark Receive the 2020 New York Society for Applied Spectroscopy Gold Medal Award 

The Eastern Analytical Symposium (EAS) Award for Outstanding Achievements in Magnetic Resonance will be presented to Arthur G. Palmer III on Monday, November 16.

received a BA in chemistry magna cum laude in 1980 from Haverford College. At Haverford, he conducted undergraduate research in the photochemistry of carbonyl carbene with Professor Colin F. Mackay. After two years working as an analytical chemist and two years teaching high school chemistry and physics, Palmer entered graduate school, first receiving his MS in Industrial Health from the University of Michigan in 1986 and then completing his PhD from the University of North Carolina at Chapel Hill in 1989. His doctoral research, conducted under the direction of Professor Nancy L. Thompson, developed the technique of high order autocorrelation in fluorescence correlation spectroscopy.

Palmer made the transition to nuclear magnetic resonance (NMR) spectroscopy during his work as a National Science Foundation Postdoctoral Fellow with Dr. Peter E. Wright at the Scripps Research Institute from 1989 to 1992. There, Palmer codeveloped, with Wright, Mark Rance, and John Cavanagh, sensitivity-enhanced heteronuclear single quantum coherence spectroscopy (HSQC) and began his first developments and applications of NMR spin relaxation to characterize macromolecular dynamics. Palmer moved to the Department of Biochemistry and Molecular Biophysics at Columbia University as an assistant professor in 1992 before being promoted to associate professor in 1998 and then to professor in 2001. Palmer currently holds the Robert Wood Johnson junior chair title and serves as interim Chair of the Department of Biochemistry and Molecular Biophysics and as Associate Dean for Graduate Affairs at Columbia University Medical Center. He is also the Director of NMR Spectroscopy at the New York Structural Biology Center.

Palmer is the author of 150 papers and the coauthor, with John Cavanagh, Wayne J. Fairbrother, Nicholas J. Skelton, and Mark Rance, of the book 

Protein NMR Spectroscopy: Principles and Practice

, now in its second edition. Palmer uses NMR spectroscopy and molecular dynamics simulations to elucidate the coupling between conformational dynamical properties and biological functions of proteins. His research interests include the development of novel methods in NMR spectroscopy, computational and theoretical analyses of protein dynamics, and applications to protein folding, molecular recognition, and catalysis. He has contributed in particular to the use of generalized order parameters for characterizing conformational entropic effects in molecular recognition, and the use of CPMG and R1r relaxation dispersion measurements for characterizing microsecond-millisecond time scale processes.

Palmer is interested in the conformational dynamic differences between mesophilic and thermophilic enzymes that contribute to differences in activity, using the ribonuclease H superfamily as a model system. Other recent applications include the mechanism of strand swapping in dimerization of cadherin cell adhesion proteins, the role of local dynamics in DNA recognition by the GCN4 bZip transcription factor, and dynamic control of the order of substrate addition in the DNA-repair enzyme AlkB.

Arthur Palmer Receives EAS Award for Outstanding Achievements in Magnetic Resonance

The Eastern Analytical Symposium (EAS) Award for Outstanding Achievements in Vibrational Spectroscopy will be presented to John A. Reffner on Tuesday, November 17. Reffner will also give a talk on “Advancing Our Knowledge Through Studies of Vibrational Spectra.”

Reffner’s scientific interests focus on uniting spectroscopy with microscopy and applying novel technologies to advance materials and forensic science. He pioneered the development of infrared micro-spectrometers, accessories, and innovative applications in infrared microprobe technology. Reffner’s scientific accomplishments are recognized by his receiving the 2016 American Society of Trace Evidence Examiners’ Edmond Locard Award, the 2015 Society of Applied Spectroscopy’s Gold Medal Award, the 2004 American Academy of Forensic Sciences award, the 2004 Paul L. Kirk Award, the 2002 New York Microscopical Society’s Abbe Memorial Award, the 2002 Georgia Microscopical Society’s Honorary Achievement Award, the 2000 Coblentz Society’s Williams-Wright Award, and the 1993 Illinois State Microscopical Society’s Emile M. Chamot Award. In 2011, Reffner was named a fellow of the Society of Applied Spectroscopy (SAS).

Reffner has authored 90 papers and four book chapters while inventing ten patents. He served as a consultant to the Connecticut State Police for over 25 years and has testified as an expert witness in criminal, civil, and intellectual property litigations. He is also on the advisory board of the Dr. Henry C. Lee Institute at the University of New Haven. His employment, since graduation from Akron University, includes B. F. Goodrich, Walter C, McCrone Associates, the University of Connecticut, American Cyanamid, Spectra-Tech, Nicolet, Thermo Scientific, SensIR, and Smiths Detection. Reffner is currently a professor of forensic science at John Jay College, which is part of the City University of New York (CUNY) in New York, New York.

The Eastern Analytical Symposium (EAS) Award for Outstanding Achievements in Vibrational Spectroscopy will be presented to John A. Reffner on Tuesday, November 17.

John Reffner Receives EAS Award for Outstanding Achievements in Vibrational Spectroscopy

Jerome Workman Jr. serves on the Editorial Advisory Board of Spectroscopy and is currently with Unity Scientific LLC. He is also an adjunct professor at Liberty University and U.S. National University. He can be reached at jworkman04@gsb.columbia.edu.

Recent collaborative research demonstrates the use of Kerr-gated Raman spectroscopy to study catalysts and catalytic reactions for investigating renewable energy sources. The approach overcomes fluorescence interference problems normally encountered using Raman spectroscopy of catalysts and can facilitate the development of renewable energy sources, such as producing gasoline from methanol.

 (1), was performed through a collaboration between the Central Laser Facility (CLF) of the Science and Technology Facilities Council (STFC), University College London, Ghent University, and the Catalysis Hub, The Catalysis Hub is a United Kingdom consortium aimed at leading the world in catalytic science.

Catalysis is an extremely important field of study in chemistry and involves the materials and processes of increasing the rate of a chemical reactions by the use of catalysts. Catalysts are the materials used to increase reaction rates, by lowering activation energies for reactions, and can be repeatedly used while not being consumed in the catalyzed reaction. Different classification types of catalysts include electrocatalysts, organocatalysts, photocatalysts, enzymes, and biocatalysts. Catalytic reactions occur in nature as well as in synthetic chemical reactions, such as in the production of petroleum products (alkylation, catalytic cracking, catalytic converters); bulk chemical production (catalytic oxidation, hydrogenation, and hydroformylation); fine chemical production (Heck reaction, and Friedel–Crafts reactions); and in food processing (hydrogenation and biocatalysis).

Natural and synthetic zeolite crystals (Figure 1) are essential catalysts, and represent the most-used catalysts by weight in the world. Zeolites are crystalline alumino-silicate, porous materials with regular molecule-sized nanopores—having a specific physical structure of channels and cavities, which affect their catalytic properties and efficiencies (their adsorption, diffusion, and reaction properties). Understanding zeolite structure and reaction properties is an important area of research in the field of catalysis.

Understanding the detailed structure and function of zeolites in chemical reactions has been an analytical challenge. The pores of zeolites may be contaminated with heavy hydrocarbons over time that get trapped within them—as contamination occurs over time the catalytic activity will decrease and eventually cease. When the zeolite is deactivated it must be replaced or reactivate using an expensive process. This entire activation and deactivation process is of keen interest to catalysis researchers.

One of the most common techniques used to investigate zeolite structure and catalysis is Raman spectroscopy. However, the fine structural information that might be available using the Raman technique is often obscured due to background fluorescence. CLF’s expertise in Kerr-gated Raman spectroscopy is providing the means for detailed spectra to be obtained without the fluorescence background problems.

Kerr-gated Raman spectroscopy uses the Kerr gate optical effect to remove most of the fluorescence background from the Raman signal when using Raman spectroscopy. The Kerr gate effect functions by plane polarizing the combined Raman scattered signal and fluorescence signal (resulting from a 1 ps laser pulse) by using a plane polarizer. Then by passing that combined signal through a 45o tilting CS2 containing cell of 2 mm pathlength (Kerr medium), the resulting signals are separated into a plane polarized fluorescence signal and a perpendicularly polarized Raman signal. By then passing the signals through a cross polarizer, the Raman scattering will pass (is transmitted) to the detector, while the fluorescence signal is blocked. Therefore the fine Raman spectral structure may be observed relatively free from the fluorescence background. The Kerr gate effect takes advantage of the time delay between the instantaneous Raman scattering signal and the delayed background fluorescence that occurs a few picoseconds or nanoseconds later.

“Kerr-gated Raman is remarkable because it makes it possible to detect tiny Raman signals from zeolite reactions that would otherwise be lost in a sea of fluorescence noise, said Professor Mike Towrie of CLF “The Ultra Laser Facility at the CLF allowed us to achieve a signal quality approximately 100 times better than if we’d used standard Raman. For me, this work has been exciting because it demonstrates the potential of Kerr-gated Raman to help answer many more questions in catalysis and in other areas such as battery science.”

Kerr-gated Raman spectroscopy is being applied to gain understanding of the potential for catalytic reaction chemistry to produce gasoline (mostly octane) from simple hydrocarbons, such as methanol. Better understanding of this reaction could result in producing gasoline from biomass fermentation as a renewable energy source—reducing both fuel production costs and environmental impact. Methanol is considered a clean energy option that can be produced from many renewable sources. A methanol molecule has only half the energy density of gasoline and, in the 1970s, the chemistry was developed to convert methanol into gasoline using a catalytic reaction involving zeolites. The size of the zeolite pores determines the type of hydrocarbon produced by the catalytic reaction—small pores produce light hydrocarbons—medium pores produce gasoline.

Using Kerr-gated Raman spectroscopy the CLF team were able to track all the stages of the reaction, in increments of three to four picoseconds, and observe a conversion of methanol to octane as longer chains of hydrocarbons were being formed. This allowed detailed observations of the entire reaction process. The Raman technique also provides information of the activation and deactivation of the zeolite catalysts. This rapid analysis technique has provided insight into the formation of polyenes as the cause of deactivation of the zeolite catalysts—a new and unexpected discovery. “I think that this will change the way people think about how these materials deactivate because, as soon as you know who the culprits are, you are able to design a strategy, said team leader Professor Andy Beale of University College London. He said, “There is a huge energy cost, as well as time cost, associated with reactivating catalysts frequently, so anything that can keep catalysts doing their job for longer will save money, energy and reduce the environmental impact resulting in greener fuels. The study could be significant for industry especially as methanol can be produced from biomass stocks meaning that gasoline may not have to come from fossil fuel stocks in the future.”

Reference
(1) I. Lezcano-Gonzalez, E. Campbell, A. E. J. Hoffman, M. Bocus, I. V. Sazanovich, M. Towrie, M. Agote-Aran, E. K. Gibson, A. Greenaway, K. De Wispelaere, V. Van Speybroeck, and A. M. Beale, “Insight into the effects of confined hydrocarbon species on the lifetime of methanol conversion catalysts,” Nature Materials 19, 1081–1087 (2020). (

https://doi.org/10.1038/s41563-020-0800-y

Recent collaborative research demonstrates the use of Kerr-gated Raman spectroscopy to study catalysts and catalytic reactions for investigating renewable energy sources.

Kerr-Gated Raman Spectroscopy is Being Used to Study Catalysis Reactions for Investigating Renewable Energy Sources 

In your paper (1), you state that single-cell inductively coupled plasma mass spectrometry (SC-ICP-MS) is an emerging methodology that holds promise to enable multielemental analysis of low-volume samples in the future. Can you explain why you believe this?

In my view, SC-ICP-MS has become a hot topic in the field of elemental analysis, and rightly so: Scientist working in the field of bioanalytics applied this approach to look into the smallest units of life. As a matter of fact, most biochemical processes take place in cells. Elemental bioanalysis in cells makes it possible to obtain deep insights into cellular processes and the biological status of specific cells. In comparison, the analysis of bioliquids mainly provides insights on a systemic level of the corresponding organism. Over the last decades, many scientists applied ICP-MS to study the elemental composition in all kinds of biofluids and tissues. Due to the latest technical developments it is now possible to achieve ever lower detection limits. Thus, it is now possible to examine individual cells and their elemental composition—at least partially. This may open a completely new field of application for ICP-MS and there are many scientists who are about to prove this.

Why is ICP-MS generally considered being the method of choice for multielemental analysis as compared to other ICP techniques (AES or OES) or more traditional atomic absorption (F-AAS or GF-AAS)?

ICP-MS is unarguably the gold standard for elemental and especially multielemental analysis. This is mainly due to the fact that this technique is extremely versatile compared to ICP-OES/AES and atomic absorption spectroscopy. Most AAS devices apply element-specific radiation sources (hollow cathode lamps) that enable the detection of a single element at the same time. Although there are some commercially available AAS instruments that allow the detection of 10-20 elements simultaneously, sensitivity limitations hamper the analysis of most trace and ultratrace elements. ICP-OES allows multielemental analysis, is relatively easy to setup, and well-suited for high-throughput analysis—however, spectral interferences can be challenging. ICP-MS allows high-throughput, multielemental analysis with the lowest-possible detection limits. It offers a linear detection range of up to 10 orders of magnitude, enables isotopic analysis (isotope dilution analysis for quantification, control of spectral interferences), and it is possible to analyze any type of sample material (gases, liquids, solids).Furthermore, high-resolution separation techniques such as HPLC, GC, CE etc. can be hyphenated to the ICP-MS. Overall, this makes ICP-MS the most powerful and versatile technique for elemental analysis.

What motivated you to focus on this specific application?

Several times, we have encountered situations, where limited sample volume was available. For example, limited volume of biofluids (blood serum or plasma) might be available in human sample cohorts for interdisciplinary clinical studies. In such cases, the principal investigator often selects the panel of analytical tests according to the required sample volume. Sample volume restrictions can also arise from the donor itself, even if there is no competing analysis. This is the case for animal models, especially for studies with mice where only a few µL of blood serum or plasma are available per animal. Since most of the published multielemental profiling methodologies require relatively large sample volumes, our aim was to provide a tool that overcomes this challenge. For this reason, in 2016 we have developed an ICP-MS based method, which allows the analysis of 29 elements in a 150 µL blood serum sample. However, we soon realized that there is a need for multielement analysis in even smaller sample volumes. This is for example the case when only small amounts of serum and sample are available (for example, in precious clinical cohorts or preclinical studies with rodents). We accepted the challenge and found that it is possible to detect 20 to 30 elements in 3–10 µL of biological fluids. These positive results have motivated us to optimize and validate the method. Finally, we have successfully applied the method in a preclinical model. The method turned out to be very easy to use, it does not require expensive or complicated changes in the experimental setup, and, above all, it has shown very good analytical performance. We then decided to publish the results of our study as well as the experimental setup in order to encourage other readers to perform multi-element analyses in the smallest sample volumes in a straightforward way.

What are some cancer-specific multielemental profiles that you have identified? What type of data analysis techniques were used to determine these profiles? Are there a few predominant elements that seem to be most often present in the mice cancer cells?

In the mouse cancer modes under evaluation, the presence of the tumor influences the serum concentration levels of various elements. Some elements, such as sulfur, calcium, manganese, zinc, strontium and molybdenum, were not affected significantly by the presence of the tumor. On the other hand, elements such as phosphorous and copper were increased in the serum samples of tumor bearing mice, independently of the tumor type. Iron, on the other hand, was depleted. These results seem to indicate that the presence of tumor systemically influences the concentration levels of some serum elements, independently from the tumor type. On the contrary, elements such as vanadium, chromium, bromine, rubidium, cesium and cobalt show trends for tumor-specific concentration changes. Furthermore, our results show that different immune T cells (CD4+ and CD8+) have specific mineral profiles reflecting their specific immune function. Moreover, the presence of a tumor seems to have an impact in the mineral contents of T cells. Indeed, we observed elemental modulations within CD8 cells that could be associated with presence of cancer, such as higher levels of magnesium and manganese and lower levels of iron, cobalt and rubidium. These findings might indicate an increased metabolic need of immune cells for Mn and Mg in the presence of a tumor.

What are the biggest challenges that you encounter in this analysis method? Are there any limitations to using this technique? What options or alternatives are available to overcome these challenges?

While the analysis of small amounts of biofluids is quite straightforward (centrifugation to remove particles and a simple dilution step), the analysis of cells is more challenging. In fact, one hurdle we faced during method development was to remove the cell sorting buffer (containing a high concentration of various elements of interest) from the cells. As large volumes of this buffer are required for a single cell-sorting experiment (roughly 10 liters in our case), it was not possible to prepare a buffer solution based on reagents which are suitable for trace elemental analysis. For a washing step, we applied filters or considered osmosis for buffer removal, but none of these sample preparation strategies proved to be suitable. Finally, applying a mild centrifugation step to form a cell pellet, followed by removing the supernatant with a pipette, provided satisfying results. However, the removal of a few microliters from an Eppendorf tube, and at the same time maintaining the integrity of a tiny cell pellet, remains the Achilles heel of the method and requires some finesse and experience.

With such small samples, is contamination an issue, and how have you overcome this potential problem?

Contamination is always a challenge in ultratrace elemental analysis. Acid-washing, working in a clean environment and under a fume hood are the minimum requirements to obtain high quality results. However, contamination is not more challenging in this method, as compared to most other ICP-MS based methods dealing with trace and ultratrace analysis. This is mainly due to the fact that a relatively moderate sample dilution of (1:10) and few sample preparation steps are applied. Contamination could arise, for example, from plastic materials. We mitigate this risk by applying an acid-washing step up front. Another, often underestimated source of contaminants are chemicals and reagents applied during sample preparation. They often contain elements (for example, iron) that enter the sample in this way and thus mix with the analytes. Due to the inherent properties of elemental mass spectrometry, it is then no longer possible to distinguish easily between endogenous and exogenous elements. This can lead to an overestimation of the element concentration. In our study we only apply buffer solutions and nitric acid during sample preparation. Thus, the overall contamination risk is relatively low.

Can you briefly summarize the results that you have achieved so far?

We have developed a quantitative analytical strategy that enables the analysis of 20 biologically relevant elements in low-volume samples (10 µL) of serum. By applying an optimized workflow, the method is also applicable for the quantification of 12 elements in a low number of sorted cells (250,000 cells). In our paper, we give detailed descriptions of the experimental setup. This enables scientist to apply the approach to study biological-relevant elements (major trace and ultratrace elements) in very small sample volumes. Applied to tumor cells, we could demonstrate that the presence of certain cancer types influences differentially the elemental composition of serum concentrations. Furthermore, we could show that different immune T cells (CD4+ and CD8+) have specific mineral profiles reflecting their specific immune function. Last but not least, the presence of a tumor effects the mineral composition of T cells.

Is there anything that you have done in your study that is different from what other researchers have done as they have examined the same problem?

Most of the ICP-MS-based approaches aiming to detect major trace and ultratrace elements in cells are challenged by the media or solvent in which the cells are transported into the plasma ionization source. If the cells are present in Milli-Q water, the “elemental background” is very low. This facilitates the detection of very small quantities of cellular elements. However, cells are prone to lyse in Milli-Q-water. This makes the cellular membranes permeable for ions and small molecules, which are eventually leaking out of the cell and changing the elemental composition of the cell. Fixation strategies, aiming to stabilize cellular membranes, can prevent lysis. Unfortunately, fixation methods tend to increase permeability of the cell membranes and consequently alter the endogenous elemental composition of the cell. Moreover, aggregation of cells is often seen after fixation and needs to be monitored. In fact, the presence of cells in the monodisperse state has to be confirmed by complementary analysis. Many of the reported SC-ICP-MS methods are overcoming this issue by using yeast cells. The use of yeast cells has two advantages: first, the cells are relatively big, meaning higher absolute quantity of elements per cell. Second, these cells are extremely robust compared to immune cells. Re-suspended in Milli-Q water, yeast cells can stay alive for a couple of hours without undergoing lysis. This timespan allows conducting SC-ICP-MS experiments with intact cells while maintaining an extremely low elemental background of the solvent. Suspensions of cells in buffer solutions, on the other hand, allow keeping the cells alive and preserve the integrity of the cell. However, such buffer solutions contain “contaminants”; for example, major or trace elements which are present in the raw materials. This makes it difficult to distinguish between “cellular” elements and elements from the buffer solution. We were able to overcome this limitation by using a sample preparation strategy that includes a washing step with a suitable buffer solution (containing a relatively low elemental background).

What are your next steps in this work? Do you know how well the discoveries of multielemental profiles in mice cancer cells may extrapolate to human cancer cells?

I am now working in a company which is rather focused on elemental analysis is food and pharmaceutical products. However, my former colleagues are continuing our research work and other scientist are working on different approaches to study trace- and ultratrace elements in cells. I am confident that rather sooner than later we will see new findings in this field, both in pre-clinical and clinical studies.

Tobias Konz is currently leading the Elemental Analysis group at UFAG Laboratorien (in Sursee, Switzerland), specializing in quantitative analysis of elements in food and pharmaceutical products (GMP and ISO environment). He studied biomedical chemistry at the Johannes-Gutenberg University (2000-2007), and completed his diploma thesis and PhD in Analytical Chemistry in the research group of Alfredo Sanz-Medel, under the supervision of Maria Montes-Bayón (University of Oviedo, Spain). In 2014, he started a professional career as ICP-MS specialist at the Nestlé Institute of Health Sciences (Lausanne, Switzerland) in the Nestlé Research organization. The main focus of his work has been to develop quantitative methods for multielemental analysis in low volume samples (biofluids) in a GLP and ISO regulated environment.

(1) T. Konz, C. Monnard, M. Rincon Restrepo, J. Laval, F. Sizzano, M. Girotra, G. Dammone, A. Palini, G. Coukos, S. Rezzi, J.-P. Godin, and N. Vannini, 

https://dx.doi.org/10.1021/acs.analchem.9b05643

Tobias Konz of Nestlé Research, Lausanne, Switzerland and various associates have developed and validated what they describe as a reliable, robust, and easy-to-implement quantitative method for multielemental analysis of low-volume samples. The ICP-MS-based method comprises the analysis of 20 elements (Mg, P, S, K, Ca, V, Cr, Mn, Fe, Co, Cu, Zn, Se, Br, Rb, Sr, Mo, I, Cs, and Ba) in 10 μL of serum and 12 elements (Mg, S, Mn, Fe, Co, Cu, Zn Se, Br, Rb, Mo, and Cs) in less than 250,000 cells, and involved the analysis of elemental profiles of serum and sorted immune T cells derived from naıv̈e and tumor-bearing mice. The results indicate a tumor systemic effect on the elemental profiles of both serum and T cells. Konz and his colleagues believe their approach highlights promising applications of multielemental analysis in precious samples such as rare cell populations or limited volumes of biofluids that could provide a deeper understanding of the essential role of elements as cofactors in biological and pathological processes. Konz spoke to us about this work.

Quantitative Methods for Multielemental Analysis in Low Volume Biofluids 

 Magazine is pleased to announce the addition of seven new members to its editorial advisory board: Karl S. Booksh, John Coates, Paul J. Gemperline, Barry K. Lavine, Igor K. Lednev, and Yukihiro “Yuki” Ozaki.

Karl S. Booksh is a professor in the Department of Chemistry and Biochemistry at the University of Delaware. He holds a BS in Chemistry from the University of Alaska and a PhD in Analytical Chemistry from the University of Washington. He is an American Chemical Society Fellow (2015) and a Society for Applied Spectroscopy (SAS) Fellow (2014), and is the president elect of SAS for 2021. His research group develops small chemical sensors capable of reliable measurements in the field or in the process chemical sensors for environmental, biomedical, and industrial process monitoring. His group also conducts chemometric analysis of collected data and multivariate sensor calibration. In terms of analytical techniques, Booksh is focusing largely on Raman, Laser-induced breakdown spectroscopy (LIBS), and fluorescence sensors with a bit of Raman imaging for fun. He is the author of over 100 peer-reviewed articles.

John Coates was educated and started his career in the United Kingdom. He first worked as an analytical chemist for Castrol Oil Company. He graduated from the Royal Society of Chemistry (RSC) and obtained his PhD in analytical chemistry at Brunel University. After moving to the United States as a senior staff scientist at Perkin Elmer Corporation, Coates accepted positions at Spectra-Tech (Stamford, Connecticut) and then at Nicolet Instruments (Madison, Wisconsin) before returning to a position at PerkinElmer’s Real-Time Systems Division (Wilton, Connecticut) a joint-venture with Dow Chemical Company (Midland, Michigan).

In 1996, Coates opted to leave the corporate world and formed his own company, Coates Consulting LLC, a consulting company focused on applied and industrial instrumentation, optical spectroscopy, and analytical instruments and sensors for dedicated applications, with a primary focus on instrument miniaturization and spectral sensors. Coates has been involved in the development of more than 100 different instrument and sensor products for dedicated applications and received the Williams-Wright Award for Industrial Spectroscopy, presented by the Coblentz Society, in 2013. Coates has 50 years of industrial experience.

Paul J. Gemperline has been the dean of the graduate school at East Carolina University (ECU) since 2009 and a faculty member in the department of chemistry since 1982. He earned his BS and PhD in chemistry from Cleveland State University. Gemperline’s area of research is chemometrics with more than 60 publications and $1.8 million in external grant funds from government and industrial sources. Gemperline's research focuses on the development of new computer algorithms and software tools for analysis of multivariate spectroscopic data. His work has led to advances in methods for monitoring, understanding, and controlling batch chemical and pharmaceutical processes. He has developed methods of cluster analysis and classification for rapid non-destructive testing of raw materials and finished products. His work with collaborators led to the development of a licensed patent for designing optical filters for chemical calibration.

Gemperline also served as the editor-in-chief of the 

Barry K. Lavine is a professor of chemistry at Oklahoma State University (OSU). Lavine’s research interests encompass many aspects of chemical analysis including optical sensors, vibrational spectroscopy, infrared and Raman imaging, and chemometrics. Lavine has published more than 115 research papers, 21 book chapters, and 16 review articles, along with being the editor for three ACS monographs. Lavine is on the editorial board of several journals including the 

. He has served as chair of the Northern New York (1997–2004) and Oklahoma (2006–2008) sections of the ACS. Lavine has also been the program chair for several meetings including SciX (1992), the Northeast Regional ACS Meeting (1999), and the Pentasectional Meeting of the local Oklahoma Sections of the ACS (2005). Lavine is the recipient of the 2015 Kowalski prize from the 

and the 2017 Chemometrics Award sponsored by the Eastern Analytical Symposium. He is also a SAS fellow.

Igor K. Lednev is a professor at the University of Albany, State University of New York. He received his PhD from the Moscow Institute of Physics and Technology and worked in several leading laboratories around the world in the United Kingdom, Canada, Germany, and Japan. Lednev accepted a faculty position at the University at Albany in 2002 and was promoted to full professor in 2013. His research focuses on the development and application of novel laser spectroscopy techniques for medical diagnostics and forensic purposes. Lednev is a cofounder of two startup companies commercializing his patented technology. He served as an advisory member on the White House Subcommittee for Forensic Science and is a fellow of SAS and the Royal Society of Chemistry. Lednev also launched a new annual National Institute of Justice (NIJ) Forensic Science Symposium at Pittcon in 2018.

He has co-authored about 240 publications in peer-reviewed journals and seven patents.

Yukihiro (Yuki) Ozaki received his PhD in 1978 from Osaka University. He joined Kwansei Gakuin University in 1989. From 1993 to March 2018, he was a professor in School of Science and Technology. Currently, Ozaki is a professor emeritus of the university. He has been a guest professor or scientist at Kobe University, Fukui University, and Riken and Toyota Physical and Chemical Research Institute. Ozaki is involved in studies of a wide range of molecular spectroscopy techniques, ranging from far-ultraviolet to far-infrared to Terahertz and Raman spectroscopy. His research focuses on both electronic and vibrational spectroscopy.

Ozaki has been a member of SAS for more than 30 years and fellow since 2013. He received several awards including the Bomem-Michelson Award (2014), Chemical Society of Japan Award (2017), The Medal with Purple Ribbon (2018), Pittsburg Spectroscopy Award (2019), and Charles Mann Award (2020).

Barry Wise received BS degrees in chemistry and chemical engineering from the University of Washington in 1982. After three years with Battelle Pacific Northwest National Laboratory, he returned to the University of Washington, where he received MS (1987) and PhD (1991) degrees in chemical engineering. Wise has authored more than 50 scientific publications, patents, and book chapters. He has also created a popular chemometrics software package, PLS_Toolbox, used by scientists and engineers worldwide. Wise is president and cofounder of Eigenvector Research Inc., which provides chemometrics software, training, and consulting. Thousands have attended Wise’s chemometrics short courses at conferences and at Eigenvector University.

Wise was named the winner of the Eastern Analytical Symposium Chemometrics Award for 2001 in recognition of his significant contributions to the field. He also received the Herman Wold Medal in Gold in 2019 for his deep commitment to the proliferation of chemometrics.

Spectroscopy Magazine is pleased to announce the addition of seven new members to its editorial advisory board.

Seven New Members Join Spectroscopy's Editorial Advisory Board

Of course, this year’s meeting is different because of our response to the presence of COVID-19. 

 There will be LIVE on-line sessions each day during the week of 

 Additionally, the EAS presents pre-recorded ON-DEMAND sessions available at any time through December 31 to those who register for the Symposium. And, be sure not to miss the on-line virtual exhibition for the latest innovations from the vendors you have come to rely on.

This year, the EAS Awards for achievements in spectroscopy recognize the outstanding contributions of Barbara S. Larsen (mass spectrometry), Arthur Palmer (magnetic resonance spectroscopy), and John Reffner (vibrational spectroscopy), and you can tune in to these award sessions, LIVE. Also live are the sponsor awards such as the SAS Gold Medal honoring Howard Mark and Jerome Workman, as well as the Ernst Abbe Award to Brian J. Ford. But there also are many pre-recorded on-demand sessions and posters on spectroscopic analysis of materials, forensic analysis, biological and pharmaceutical analysis, microscopy, Raman imaging, LIBS, and many more.

Two highlights of the EAS in years past have been the keynote lecture and the plenary lecture, and this year’s lectures should be exceptionally entertaining for attendees. The keynote lecture by Eric Green of the National Institutes of Health is titled “The Human Genome Project was just the Beginning: Research Opportunities at the Forefront of Genomics.” The plenary lecture, “The Fascinating Impact of Nanoscale Structure on Chromatography and Mass Spectral Ionization,” will be given by Susan Olesik, this year’s winner of the EAS Award for Outstanding Achievements in the Fields of Analytical Chemistry. Her lecture combines two themes that should interest a wide audience. In addition, this year there is a special lecture presented by Adam Lanzarotta of the USFDA on the “FDA’s Role in the 2019 Vaping Crisis.” These three lectures focus on important issues in science and how it affects the world around us.

The Eastern Analytical Symposium is known for its large suite of short courses tailored to the needs of analysts. This year we are proud to continue the tradition of short courses on a wide range of traditional and novel topics in analysis. Whether it’s gas or liquid chromatography, hyphenated methods, spectroscopic methods including imaging, NMR spectroscopy, FT-IR spectroscopy, or topics like communication or process analysis, there is a course at EAS for you!

These will be presented in a LIVE video format that allows interaction with the instructor, over several weeks, allowing interested persons to attend multiple short courses.

, for the latest news and registration info for this year’s virtual EAS. Be sure to take advantage of the discounted pricing we offer to those who register early!

Once again, the Eastern Analytical Symposium takes the spotlight November 16–19, providing analysts with the latest developments in areas ranging from biopharmaceutical analysis to materials characterization, from quality assessment to green analysis, and from environmental contaminant determination to antibody analysis, to name a few of the many areas covered.

The 59th Eastern Analytical Symposium

The Society for Applied Spectroscopy (SAS) Atomic Section is proud to honor four deserving students with the 2020 SAS Atomic Section Student Awards. These awards provide the winning students with the opportunity to present their work at the conference and normally include travel funding to attend the conference. This year, the winners will present during an on-demand access session as part of the SciX 2020 virtual conference. The awards also include a two-year membership to the society. The four winners are listed below.

who is a student at Rensselaer Polytechnic Institute under Prof. Jacob Shelley, will present his work on “solution-cathode glow discharge ionization sources for mass spectrometry.”

of the University of Natural Resources and Life Sciences Vienna (BOKU), who is studying under Prof. Thomas Prohaska, will present her work on “LA and MC-ICP-MS for isotope analysis of bone for biomedical applications.”

, a student at the University of Münster, under adviser Prof. Uwe Karst, will present his work on “LC–ICP-MS for Gd speciation in surface and drinking waters.”

 of the University at Buffalo, The State University of New York, whose adviser is Prof. Steven Ray, will present her work on “Exploration of microelectrochemical devices as temporal gating devices for LIBS and LAMIS.”

More information about the awards can be found on the SciX conference 

The 2020 SAS Atomic Section Student Awards

In this investigation, two conventional peristaltic pumps are compared with a new pump based on the “easy click” principle using a simultaneous ICP-AES instrument with standard operating conditions. It is found that the figures of merit achieved are quite comparable for all three pumps. Relative standard deviations (RSDs) range between 0.2% and 1.8%, and limits of detection as low as 0.1 µg/L have been achieved , demonstrating that the easy click principle of the new pump does not compromise the analytical figures of merit.

Atomic spectroscopy has a long history that starts with Sir Isaac Newton (1643–1727) when he was theorizing about color in 1704 (1). He introduced the idea of the “spectrum,” which he believed was made up of different components of light.

Many years later, in 1814, German physicist Joseph von Fraunhofer paved the way for modern absorption spectroscopy when he interpreted the black lines in the sun’s spectrum (2). In the later nineteenth century, German chemist Robert Bunsen, together with physicist Gustav Kirchhoff, examined the colors of the spectrum of a flame, and laid the foundation for today’s atomic spectroscopy (3).

In 1955, Sir Alan Walsh published his work on atomic absorption spectroscopy (AAS) (4). Since then, this analytical method has been in daily use in many thousands of analysis systems to determine the concentration of various elements, primarily in liquids. Considerable efforts were made to develop AAS from a single-element method into a multielement method (5), but other techniques, based on plasmas instead of a flame, namely inductively coupled plasma-atomic emission spectroscopy (ICP-AES) (6) and inductively coupled plasma–mass spectroscopy (ICP-MS) (7), were used to utilize element emissions or ionization of the analytes for today’s multi-element analysis.

All of these methods mentioned are quite similar in their construction. Each method ismade up of a system for introducing the sample, comprising of a pump and an atomizer (such as an aerosol generator) to transfer the sample into the hot zone (flame or plasma), a spectrometer (spectrograph, monochromator, or mass spectrometer), a detector, and a control computer complete with software for operating the machine and analyzing the results. Although analysis systems from different vendors differ radically, some components are nevertheless very similar. This is true of the pump systems used to feed the liquid sample into the nebulizer or the atomizer. As a rule, users take little notice of these components, and regularly fail to maintain and monitor them properly, even though they can. Despite the small size of the nebulizer and atomizer, these small components have a significant impact on the results of the analysis.

Peristaltic pumps are based on the principle of peristalsis, which often occurs in biological processes or organs such as the esophagus, where it transports liquids. In instrumental analysis, peristaltic pumps can be used to transport liquid samples. The basic principle by which a sample is transported is based on the alternate compression and relaxation of elastic pump tubing. The pump tubing is passed around a roller head, and pressed against the roller head with a curved pressure plate. The tubing is pressed so tightly against the roller head that it is completely sealed. When the tubing returns to its original shape behind the roller as the pump head rotates, a vacuum is created, drawing the liquid sample into the tube. Further rollers on the pump head seal the pump tubing again to form a closed segment of liquid. The rotation of the pump head drives the fluid forward in the tubing, thus causing it to flow.

The use of peristaltic pumps offers the advantage that there is no direct contact with the liquid sample at any time. Furthermore, as already described, peristaltic pumps allow constant delivery rates. As a result, these pumps help alleviate viscosity transport variations of different samples. Peristaltic pumps are available in a wide variety of designs, with significant differences in the size of the pump head and the number of rollers. The rotation speed of the pump head is usually infinitely variable, so that, depending on the inner diameter of the pump’s tubing and the rotation speed of the pump head, samples can be delivered at precise rates from a few microliters up to several milliliters per minute.

One problem that arises when using single-channel peristaltic pumps is the pulsation of the sample liquid, which can affect the aerosol generation process in the nebulizer used,(8,9)and thus will have an impact on the stability of the signal intensity measured. When a roller contacts the pump tubing, the sample liquid is displaced on both sides. The excess pressure in the tubing accelerates the sample liquid briefly, resulting in pulsating delivery to the downstream atomizer. Fluctuating delivery rates can thus potentially have a negative impact on the precision as well ason the detection threshold of the method used. When the tubing relaxes again, the volume available to the sample liquid in the tubing increases, intensifying pulsations.

A pulsation-damped pump can be used to reduce pulsation. Pulsation-damped pumps consist of at least two half-channels, with the rollers of each half-channel arranged in such a way that they are phase-shifted. This arrangement means that each peak of one half-channel is canceled out by a valley of the other half-channel. Peaks arise from acceleration of the sample liquid when the pump tubing is compressed, whereas troughs result when the pump tubing relaxes. Ideally, the pulsations of the individual half-channels cancel each other out when they are merged, so that a constant sample flow is delivered to the atomizer.

In a previous investigation, the noise spectra of different peristaltic pumps were measured, and it was shown that the noise frequency and amplitude strongly depend on the rotation speed, the number of rolls in the pumping head, and the pressure by which the elastic tubing is pressed against the roller head (10).For many commercial peristaltic pumps, this tubing pressure, which is used to press the pressure plate against the elastic tubing, will usually be increased while the tubings are altered or optimized to reduce pulsations. The rolls, meanwhile, can be adjusted manually. A new alternative is pumps with preselected settings, which do not need adjustment at all, and the required pressure is achieved by use of a spring,allowing faster changing of tubing and no need for optimization or control of the pressure (11).

This investigation compares three different peristaltic pumps to see how the analytical figures of merit, such as detection limit (DL), background equivalent concentration (BEC), and the relative standard deviation (RSD) of wavelength intensity measurements, depend on peristaltic pump conditions. In this study, multielement standards are applied for measuring 10 selected elements simultaneously using standard operating conditions of an ICP-AES instrument. The elements are selected to cover a broad range of excitation energies, and should cover the whole mass range from lowest to highest. 

Stock solutions of two multielement standards with 24 elements each (Merck VIII and XVI Certipur multielement standards, Merck Millipore) with a concentration of 100 mg/L plus 2 mL concentrated HNO3 (stock solution) were diluted in bi-distilled water acidified with HNO3. The stock solutions were diluted in bi-distilled water, and two different concentrations were diluted: concentration I:2.5 µg/L; concentration II: 25 µg/L were prepared for each element. These concentrations are selected to be 10 times or 100 times above the instrumental DL provided by the manufacturer.

For all measurements, a Spectro Arcos (12) (Spectro Analytical Instruments GmbH) simultaneous measuring optical emission spectrometer with inductively coupled plasma excitation (ICP-AES) was used (13). The instrument includes a Paschen-Runge mount optical system, where all elemental lines are focused onto a curve, called a Rowland circle, on which a linear array of electronic detectors is installed covering the wavelength range from 130 to 770 nm. The instrument provides two different orientations of the plasma source, and thus can be easily operated in radial or axial observation mode. All measurements presented here were performed in axial observation mode.

The following plasma and operational conditions were selected: a plasma forward power: 1400 W, a plasma gas flow rate at 13 L/min, a Nebulizer flow rate at 0.85 L/min; a single measurement time at 28 s. A crossflow nebulizer (AHF Analysentechnik) was used for all investigations.

For wavelength selection, wavelengths provided by the instrument manufacturer’s software were selected. During the blank measurement, the background structures in the wavelength region were evaluated to account for any spectral interference.

For calibration, three intensity measurements with 10 and 4 repetitions were performed, consisting of a measurement of the blank and measurement of two standards with concentrations of 2.5 µg/L and 25 µg /L, respectively.

Three different peristaltic pumps were selected for this investigation: I) the peristaltic pump of the Arcos device, and II) a Perimax peristaltic pump (Spetec GmbH) that is externally operated. The pressure of the pumping head of both were optimized before measurements, as to give lowest RSDs. The third pumpwas an “Easy Click” peristaltic pump (Spetec GmbH), also externally operated. All pumps were connected to an auto-sampler (Asx-260 Cetac).

All pumps were operated using a sample up-take rate of 0.8 mL/min, controlled by a volumetric measurement. For all experiments new tubing (ID color code: orange-orange, Spetec GmbH) was used, except in the Spectro device; here the tubing was in use for more than a fortnight, and this “matured” condition served as a reference value used to see if old tubing compromised the figures of merit.

For each pump the following measurement procedure was applied: First, a blank measurement was performed, and then two multielement solutions with concentrations of 2.5 µg/L and 25 µg/L were measured.

 = 10) repeated intensity measurements for at least 5 preselected lines per element were performed. The calibration data for all lines are compiled in Table I, and the number of wavelengths is reduced to a single one (indicated in Table I) to compare all three pumps. However, the total measurement time, and time needed for calculations exceeded more than 60 min, so that the number of repetitions was decreased for all further measurements to 

 = 4. As a result, the final measurement and calculation time of 25 min was achieved. Standard conditions were chosen as the integration time for each element.

Because the peristaltic pump of the Arcos system was operated with a higher pumping speed in between intensity measurement cycles, the washout phase was doubled for the Perimax and “Easy Click” pump, which were operated manually. However, the first run of a new measurement series showed a higher concentration for these two pumps, with much higher RSD, DL, and BEC values, an indication that the sample introduction system was not in a stable equilibrium. Therefore, the first run of each series of new intensity measurement has been deleted, and thus data is given for three (

Except for Se, several lines were proposed by the software of the Arcos system for most elements, and were confirmed after a blank measurement to evaluate the background structure. For all lines selected, calibration data are available, but for the comparison of the three different pumping systems, a single wavelength with the lowest DL was selected, provided the correlation coefficient was satisfactory. Selected lines, used further on, are shown in the last column of Table I, with their abbreviations.

The stability of the plasma was controlled manually using the Ar wavelength at 430.010 nm, and the resulting RSD measured was always equal or better than 1% for all pumps and all concentrations measured.

Comparison of Analytical Figures of Merit for Three Different Peristaltic Pumps

Results for the analytical figures of merit for of all three pumps are compiled in Table II. Data provided includes the DL, BEC, and the RSD. The latter is calculated as mean value from the RSDs of both concentrations used for calibration.

As stated before, the original peristaltic pump of the Arcos system was operated with matured peristaltic tubing. Nevertheless, all RSD values (shown in Table II) calculated are better than 1% (except Cr: 1.4%). Blank values (not shown) are slightly higher by 10–20% compared to new tubing (likely because the tubing was extensively used for analysis of highly concentrated digestions of steel and alloys of Al, Cu, and Ni). However, DL and BEC do not significantly deviate from the values measured for the two other pumps. The Perimax pump, for which the pressure plate was manually adjusted to the lowest pulsation setting and for which new pumping tubing were used, showed the best RSD values for all elements, being better than 1%. Even the Easy Click pump with manufacturer settings showed relatively good RSD values for some elements very close to the values achieved for the Perimax pump. This result demonstrates that the manual alignment of the pressure block does not significantly improve the figures of merit, and thus is not needed if a pump with the lowest maintenance is needed. For the lines selected, all DL values are lower than 5 µg/L (except Bi and Se). For Bi, the DL could be improved by more than a factor of two mainly using new tubing, which also demonstrates that memory effects did not significantly worsen the analytical figures of merit. Finally, it should be mentioned that all three pumps tested are very comparable concerning their analytical figures of merit. In particular, low RSD values were achieved in this experiment for all pumps investigated, and can be attributed to the simultaneous detection capability of the instrument used in this investigation. Such low precision is required for traceability studies. Applying a precision measurement method for element contents, developed using ICP-AES, combined measurement uncertainties between 0.05% and 0.1% can be achieved (14).

In this investigation, three different peristaltic pumps were compared using an ICP-AES instrument with simultaneous detection for all elemental wavelengths of interest to demonstrate that a peristaltic pump based on an “easy click” adjustment will not compromise the analytical figures of merit. It was found that comparable analytical figures of merit can be achieved for all three pumps using standard operating conditions and very low standard deviations (below 1%) can be achieved for all pumps, if simultaneous detection of the intensity measurements is applied. For multielement analysis, such very low standard deviations and LOD values can only be achieved with ICP-AES operated with peristaltic pumps, and are essential for the development of new standard reference materials (15).

Opticks or, a treatise of the reflexions, refractions, inflexions and colours of light. Also two treatises of the species and magnitude of curvilinear figures. 

https://archive.org/details/McGillLibrary-104448-118/page/n8

Analytical Atomic Spectrometry with Flames and Plasmas

R. S. Houk, V. A. Fassel, G. D. Flesch, H. J. Svec, A. L. Gray, and C. E. Taylor, 

J. Greffin, N. H. Bings, N. Jakubowski, and F. Rickert, 

https://www.spetec.de/downloads/Datenblatt_ECC_EasyClick_Compact.pdf

Spectro. Ametek–Materials Analysis Division. 

https://www.spectro.com/products/icp-oes-aes-spectrometers/arcos-inductively-coupled-plasma

A.G.T. Gustavsson, A. Montaser, and D. Golightly, 

Inductively Coupled Plasmas in Analytical Atomic Spetrometry

 (Wiley-VCH, New York, New York, 2nd ed., 1992).

H. Kipphardt, R. Matschat, O. Rienitz, D. Schiel, W. Gernand, D. Oeter, 

Certification Report of BAM-M319: A new AlMgSc powder; 

Technical Report for Bundesanstalt für Materialforschung und -prüfung (BAM): Berlin, Germany, December 2019.

are with Spetec GmbH, in Erding, Germany. 

are with Federal Institute for Materials Research and Testing (BAM), in Berlin, Germany. Direct correspondence to: 

Inductively coupled plasma–atomic emission spectroscopy (ICP-AES) relies on the use of a peristaltic pump for sample introduction. Here, two conventional peristaltic pumps are compared with a new pump based on the “easy click” principle for the analytical figures of merit.

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