John Chasse

Non-destructive mobile spectroscopic instrumentation is proving useful for examining components of cultural heritage objects—such as fibers, pigments, dyes, and inks—for quantitative and qualitative results. Mary Kate Donais of Saint Anselm College, in Manchester, New Hampshire, recently conducted a study using portable spectroscopy techniques to characterize historic fabrics from a turn-of-the-19th century New England mill that belonged to the Amoskeag Manufacturing Company, one of the largest textile producers in the world at its prime. We recently spoke to Donais about this work.

How did the opportunity to examine these samples come about?

I attended an exhibit opening featuring locally made quilts at our local history museum. I spoke to the co-curator on the exhibit about our work with cultural heritage and portable spectroscopy, and she was intrigued. The museum’s director overhead our conversation, and mentioned the fabric sample books in the museum’s collections. We were all hooked!

Having access to both the handwritten dye recipes and the corresponding fabrics was a perfect coming together of history and chemistry. The first part of the project involved a history student examining the recipes, and doing the archival research to make some sense of them from a historic perspective. The next step was to examine the fabrics using spectroscopy to try to connect the chemical information to the written word. The terms used for dye production at the turn of the century are not those used today. So, verifying things through spectral information was our main goal.

Were there any challenges using Raman spectroscopy in the study? 

Raman spectroscopy can damage more delicate materials, including natural fibers, if the laser power is too high. So, yes, we were concerned about using Raman to examine the fabrics. We were able to find some fabric scraps from the same time period to explore different instrument settings, and to make sure we didn’t cause any burn holes. As it turned out, however, we were not able to detect any Raman signal for the dyes. This is likely due to their low concentrations. Portable X-ray fluorescence (XRF) was much easier to use, and produced much more encouraging results. The biggest challenge with the XRF was its instrument window size, which allowed us to only examine certain fabrics with larger single-dye areas in the patterns.

What conclusions were you able to draw from these findings?

We have identified some specific fabric colors that have similar elemental profiles. For example, red, maroon, and brown fabrics all produced signals for iron. This suggests the possibility of a common iron-containing chemical within these dye processes.

We need to follow up with a more careful examination of the dye recipes, and spend more time trying to link the spectroscopic information to the turn-of-the-19th-century terms and documented dye processes. Also, we had some success with Fourier transform infrared (FT-IR) microscopic analysis of a few of the dyes. While not a portable technique, the results are encouraging, and worth further efforts.

You have also studied pigments found on frescoes at various sites in Italy (1), as well as Roman glass studies (2). How did the challenge of these studies differ from the New England study?

Each different sample type has given our research team the opportunity to learn about a new cultural heritage material, and how best to approach its characterization. Each has had its own unique challenges. The fresco data were collected in a field laboratory, which had a lower level of control compared to a typical science laboratory. To better understand the Roman glasses, we needed access to instrumentation such as a micro-Raman spectrometer not available in our college’s laboratories. Collaboration with Peter Vandenabeele’s group at Gent University solved that situation.

(1) M.K. Donais, D. George, B. Duncan, S.M Wojtas, and A.M. Daigle, 

(2) M.K. Donais, J. Van Pevenage, A. Sparks, M. Redente, D.B. George, L. Moens, L. Vincze, and P. Vandenabeele, 

 is a professor of chemistry at Saint Anselm College in Manchester, New Hampshire. ●

Articles

Chemistry can help us understand the past.

Using Mobile Spectroscopic Instruments to Characterize Historic Artifacts

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 

Faced with the COVID-19 pandemic, the American Society for Mass Spectrometry (ASMS) Board canceled the face-to-face ASMS Conference on Mass Spectrometry & Allied Topics, originally scheduled for May 31 to June 4 in Houston, Texas, and announced that they would shift the program to an on-line format. “Although the program would be delivered in a new and different manner, we remain committed to hosting and sharing brilliant science for a re-imagined ASMS 2020,” Richard A. Yost, the ASMS president, said in a statement. 

	With the event redubbed “The ASMS 2020 Reboot,” talks and posters will be presented in a virtual and interactive format using the familiar on-line planner and mobile app tools used at the annual conference in past years, with a schedule as follows:

	•  On-demand videos of orals will begin on June 1.

	•  Poster PDFs and optional poster presentation videos will also begin on that date.

	•  Live webinars will be conducted for plenary lectures, tutorials, award lectures, and presentations, approximately 50 workshops, with live question-and-answer (Q&A) sessions for each of the planned 64 oral sessions, and the annual ASMS meeting (including board updates and additional award presentations.) These live webinars will be scheduled Monday–Friday, June 1–5 and June 8–12, from 10:00 am to 3:00 pm+ Central Daylight Time (CDT) on most of these days. Optional one hour Corporate Member activities will be held at start and end of each day.

	•  The live webinars will be in the format of a “watch party” of each oral session (6 talks) followed by live Q&A with speakers. Attendees may also watch the talks individually on-demand at any time beginning June 1, but still join any Q&A at the scheduled times during the week of June 8.

	Highlights of the Conference are outlined below.

	•  Two tutorials will be conducted. From 12:30 to 1:15 pm CDT, “Single-Cell Mass Spectrometry” will be presented by Peter Nemes of the University of Maryland, College Park, and from 1:30 pm to 2:15, “Glycoprotein Analysis for Understanding Human Disease” will be presented by Heather Desaire of the University of Kansas.

	•  A special keynote lecture, “Is There Still Gender Bias in Academic Science (and Does It Matter)? What the Scientific Studies Say,” will be delivered by Corinne Moss-Racusin from Skidmore College from 1:30 to 2:15 pm CDT.

	•  From 2:30 to 3:30 pm CDT, the Opening Plenary Lecture, “Mars 2020,” will be delivered by Patricia M. Beauchamp, the Chief Technologist of the Engineering and Science Directorate,at the Jet Propulsion Laboratory of the California Institute of Technology.

	•  From 9:00 to 10:00 am and again from 3:00 to 4:00 pm CDT, there will be featured corporate member activities, including on-line seminars, product launches, and demonstrations

	•  The first 16 of 56 webinar-style workshops will be conducted by interest groups or independent organizers, in two sessions, with workshops 1–8 held concurrently from 10:00 to 11:30 am CDT, and workshops 9–16 held concurrently from 12:00 to 1:30 pm CDT. This schedule will continue with 16 workshops per day, Tuesday through Thursday, with 8 on Friday.

	•  From 1:45 to 3:15 CDT, The Al Yergey MS Scientist Award will be presented to Rachel Ogorzalek, a research biological chemist at UCLA. This will be followed by the Award Lecture for the John B. Fenn Distinguished Contribution in Mass Spectrometry Award, presented by Michael L. Gross, of Washington University in St. Louis, Missouri.

	•  Corporate events will be held 9:00–10:00 am and 3:15–4:15 pm.

	•  From 1:45 to 3:15 pm CDT, Research Awards will be presented to Jace Jones of the University of Maryland, Miklos Guttman of the University of Washington, and Ian K. Webb of Indiana University and Purdue University. Also, the Research at Primarily Undergraduate Institutions (PUIs) Award will be presented to Christine Hughey of James Madison University in Harrisonburg, Virginia, and the Biemann medal will be presented to Ying Ge, a Professor of Cell and Regenerative Biology and Chemistry at the University of Wisconsin at Madison.

	•  Workshops 17–24 and 25–32 will be held from 10:00 to 11:30 am and 12:00 to 1:30 pm CDT.

	•  From 2:00 to 3:30 pm CDT, awards for Postdoctorate Career Development will be presented to Juan Aristizabal Henao of the University of Florida in Gainesville, Florida, Wout Bittremieux of the University of California–San Diego, Kevin Clark of the Beckman Institute for Advanced Science and Technology (part of the University of Illinois at Urbana-Champaign), Kelly Karch of the Ohio State University, and Lindsay Pino of the University of Pennsylvania. In addition, the Ron Hites Award for Outstanding JASMS Publication will be presented to Stephen J. Valentine of West Virginia University and his co-authors Samaneh Ghassabi Kondalaji and Mahdiar Khakinejad for their paper, “Comprehensive Peptide Ion Structure Studies Using Ion Mobility Techniques: Part 3. Relating Solution-Phase to Gas-Phase Structures.”

	•  Workshops 33–40 and 41–48 will be held from 10:00 to 11:30 am and 12:00 to 1:30 pm CDT.

	•  The ASMS plans a 4-hour virtual “exhibit hall” from 12:00 to 4:00 pm CDT. This will be a specific timeframe when the society encourages all registrants of the Reboot to peruse exhibitor listings in the mobile app or on-line planner. ASMS corporate members are encouraged to host their own chat room or event during this period. Registrants can look for links within each Corporate Member or Exhibitor listing in the mobile app or on-line planner.

	•  From Monday through Thursday of the second week of the conference, two groups of oral sessions (eight sessions conducted in parallel in each) will be conducted from 10:00 am to 12 noon and from 1:15 to 3:15 pm CDT.

	•  These oral presentations will be followed by live Q&A periods from 12:15 pm to 1:00 pm and 3:30 to 4:15 pm, respectively, with one Q&A period covering the six talks in each oral session. Registrants may submit questions via the on-line planner or mobile app. Attendees may also watch the talks individually on-demand at any time beginning June 1, but still join any Q&A at the scheduled times during the week of June 8.

	•  From 10:00 to 11:00 am CDT, Stephen Brusatte of the University of Edinburgh will give the closing plenary lecture, “New Dinosaur Discoveries.”

	The deadline to register is May 22. The society hopes to offer late registration at increased fees, but, as we go to press, they are not certain that this will be an option. On-demand content will remain available to registrants through August 31.

	More information, including on-line event schedules, can be found at 

https://asms.org/conferences/asms-2020-reboot

A preview of this year’s ASMS conference, in its new on-line format.

The 2020 ASMS Conference Moved On-line in the Face of the Covid-19 Pandemic

The Clara Craver Award, awarded annually by the Coblentz Society, was named after Craver in recognition of her pioneering efforts in promoting the practice of infrared vibrational spectroscopy, and recognizes the efforts and contributions of young professional spectroscopists in applied analytical vibrational spectroscopy. The 2019 recipient, Xiaoyun (Shawn) Chen, a senior research scientist working in the Core R&D Analytical Sciences department of the Dow Chemical Company,has been leading Dow’s global optical spectroscopy technology network since 2013, and also the molecular structure capability since 2016, solving a broad range of problems and improving many different types of R&D and production processes, introducing many colleagues to the benefits of spectroscopy for their applications. Chen recently spoke to 

You have over a decade of experience in spectroscopic and chemometric method development for industrial research and development (R&D) and manufacturing projects, focusing on in situ reaction monitoring. What motivated you to focus on this area??

	Let me begin with how I got started. It was probably around my third year at Dow, and I was working on whatever projects that happened to come my way, when my mentor, Anne Leugers, handed me two attenuated total reflectance (ATR) dipper probes, which were no longer needed by another group, and told me to explore whether I could make use of them. By chance, several colleagues in our engineering and process science group reached out to us to monitor a low-temperature reaction that they could not seem to grasp with conventional off-line methods such as gas chromatography (GC), liquid chromatography (LC), or nuclear magnetic resonance (NMR) spectroscopy. We borrowed another Fourier-transform infrared (FT-IR) instrument from our process analytical group, so that we could use the ATR dipper probe to monitor that reaction. In situ monitoring immediately helped us to detect and prove the existence of a highly labile intermediate, which explained why earlier off-line analysis failed. The focus of the project then shifted to characterizing the reaction kinetics for process optimization, and, as a result, we needed to find a way to quantify the concentration of all reaction species. I was very fortunate that Randy Pell, a world-renowned chemometrician, became my mentor in chemometrics, and together we were able to apply several chemometric tools such as classical least squares (CLS) and partial least squares (PLS) to quantify all the reaction species within the complex mixture. This work was later published externally (1)

	So, that was how I got started-as a confluence of instrument and probe availability and project need. I was truly amazed by how useful and enabling in situ spectroscopy turned out to be. The results from in situ infrared (IR) substantially impacted the direction of that particular project and the work of multiple PhD-level process chemists and engineers. As encouraged by my mentors and my leaders, I started to make an intentional effort to further explore and identify similar opportunities. Very quickly, it became apparent to me that the in situ spectroscopy project was not a lucky one-off, but that there were actually many projects that would benefit. Even though people might not know how they could benefit from in situ spectroscopy, I took it upon myself to champion the application of in situ spectroscopy throughout Dow, and even outside. Since then, I just became naturally drawn to that method, and often had to force myself not to be solely focused on in situ spectroscopy. I truly believe that in situ spectroscopy can be a revolutionary tool for process monitoring.

How broad is the range of projects that you work on? Are the projects very similar to each other, or diverse?

	Extremely broad. Let me start with types of projects. Currently, I have several projects dealing with silicone, a few dealing with catalysts ranging from zeolites to MOF, one related to radical polymerization, one related to polyurethane foaming, several related to ethylene polymerization, and several related to customer applications, such as paper coating and airbag coating, among others. In terms of commercialization stages of these projects, they may range from early stage concept-shaping, to process development, to customer applications. There is never a dull moment as far as projects are concerned. The only common theme among them all is that they all can benefit from the use of optical spectroscopy.

What are the biggest challenges you tend to encounter in your work?

	Time management, motivating others, and delegation. There are many things you need to do well as an industrial analytical scientist. First, you need to make sure that you are working on important and relevant research topics. In my current role, I also need to make sure that we keep abreast of the latest analytical instrument development, so that we can solve the toughest analytical problems with the newest tools. We also need to deliver on existing projects, look out for new projects, document past projects, and mentor new people. Whether you can manage your time well among all the above-mentioned tasks is critical in determining how fulfilled, productive, and successful you can be. I forgot to mention that additionally you may also need to maintain an external presence, and I do that by serving as the newsletter editor for the Society for Applied Spectroscopy (SAS), and on the board of the Coblentz Society, and by continuing to publish in peer-reviewed journals. Motivating others and delegation are things that aren’t necessarily taught at graduate school, but become increasingly important as you progress through your career. They are often easier said than done, and I am fortunate to have several great leaders and mentors who have been coaching me throughout this process. I don’t feel I am an expert in them yet, but am trying very hard to be better at them.

You recently published a study about monitoring polyimide production using a combination of in situ infrared and Raman spectroscopy (2). Why did you use both techniques in the study? What was different about what the two techniques enabled you to see? Can the results of that study guide your choice for IR or Raman spectroscopy for future studies?

	The short answer to your first question is “because we can.” I routinely take an IR, Raman, and near-infrared (NIR) spectrometer with me when I visit my colleagues at their labs. Sometimes there’s a clear winner regarding which type of spectroscopy will be the best fit, and we’ll just use that. Just as often, we cannot really predict which technique will work best, and then we try all of them. Which technique is the most appropriate also depends on the focus of the project, which may continue to shift as we make progress.  Often optical spectroscopy may not be the right tool, and then we’ll bring in other analytical tools as well, though that’s probably outside the scope for this interview. You’ll have to read that paper to see our exact findings. For this particular study, I would say both techniques would eventually lead to similar findings, though your perspective into the reaction progress would be very different, due to the different selection rules. Another advantage of using such a broad range of techniques lies in the insights potentially offered by them. There have also been numerous times when we originally set out to solve one problem, but discovered something totally unexpected, which led the whole project to take on a new direction.
	
	

What do you consider to be the most satisfying aspects of mentoring junior spectroscopists, as well as introducing those unfamiliar with spectroscopy to the techniques?
	

As I am starting my 12th year with Dow, I am also starting to take on new roles, and one of the most important ones is to mentor young people coming to our group. I feel very lucky that I have the chance to interact with the brightest minds coming out of graduate school, and I feel especially privileged to see that such bright young people actually take on my advice as they start to navigate their first “real world” job. Seeing their maturing into driven and motivated researcher is the most satisfying part. As for introducing spectroscopy to those outside the field of spectroscopy (which is the case for ~98% of the colleagues I interact with), that’s almost an infinite source of joy for me. I can still vividly remember the first time when my friend Doug Bland told me that he didn’t believe my in situ IR results, because they didn’t line up with the earlier GC results he had been getting for two years, and his subsequent “conversion” and full embracement of in situ spectroscopy. Changing people’s minds and attitudes is often the most challenging part, but definitely the most rewarding part when you manage to do so. I now have many colleagues who no longer treat in situ spectroscopy as the last resort after they cannot use GC or LC, but rather first try to monitor their reactions with IR or  |||||||||||Raman, and only move on to GC or LC |when IR and Raman don’t work sufficiently well (which does happen from time to time). I’m very proud of this.

What do you think are the aspect of working in industry that scientists in academia don’t understand or appreciate?

	I am not sure whether it is true that academic scientists don’t understand or appreciate industrial scientists. Everyone has his or her own focus and perspective. Even within my own group, I don’t think I always understand or appreciate the importance of another fellow spectroscopist’s work. For example, I have fellow spectroscopists who spend all their time in QC labs or QC method development, and colleagues who devote themselves to process analytical, and still others whose focus was on the data management side, such as library, data communication, and chemometrics. I think we all need to put ourselves into others’ shoes to really appreciate each other more. Along the same lines, maybe it’s really the diverse type of work we do in industry that may be something not fully understood or appreciated by outsiders. We also face very different types of pressure in industry. While we usually do not get stressed out by funding or teaching, there are many other things that you have to keep abreast of to do your job well, such as keeping up with the latest technology development, ensuring a robust project pipeline, creating a roadmap to ensure that we have the most relevant capabilities matching the company’s direction, and last, but not the least, meeting the ever-changing customer and market needs.

 28(5), 319-489 (2014). DOI: 10.1002/cem.2507

 71(9), 1-8, (2017). DOI: 10.1177/0003702817700427

Xiaoyun (Shawn) Chen of Dow Chemical solves a range of analytical problems in R&D and production processes using in situ spectroscopy and chemometrics.

John Chasse

Articles

Using Mobile Spectroscopic Instruments to Characterize Historic Artifacts

Quantitative Methods for Multielemental Analysis in Low Volume Biofluids

The 2020 ASMS Conference Moved On-line in the Face of the Covid-19 Pandemic

Advancing In Situ Applications of Spectroscopy in an Industrial Setting