Q: Do you use MS as a stand-alone technique or as a detector for LC or GC? Describe the types of MS analyses and experiments you run.
A: Kevin Soulsbury: I use both GC-MS and LC-MS. In a college setting, most of the experiments I do are education-related, for example, scan/SIM mode analysis, basic introduction to LC-MS and GC-MS, and differences between ESI and APCI in LC-MS. We carry out simple quantitative analyses using internal standards, amino acid determinizations using the Phenomenex EZfaast kit, and theoretical experiments involving TOF-MS. We also occasionally work with other collaborators on a variety of GC-MS and LC-MS projects typically related to herbal or food analysis.
Shaun Loeffelman: I use the MS as a detector for GC. Full scan and selective ion monitoring (SIM) modes are used in analyses. Our experiments employ MS for both qualitative and quantitative purposes. For instance, MS identifies analytes in unknown samples, as well as analytes in complex matrices. We have used the MS as a detector for leachable chemicals in toys; to measure contaminants in food, packaging, and consumer products; and to identify components of off-odors, off-flavors, or foreign particles.
Suraj Saraswat: Most of the time, we use MS as a detector for LC separation. We separate peptides or proteins using 1-D or 2-D LC, and identify and characterize the contaminants through MS. We work on identifying labels on proteins and the extent of labeling.
Chris Singleton: We use MS as a detector for both LC and occasionally for GC. We use LC-MS for biopharmaceutical analyses, studying peptides and proteins and their modifications. Our instruments run the gamut from single quadrupole to triple quadrupole/QTrap, TOF and Q-TOF, orbital and linear traps, and ion mobililty, so we have all of the common mass analyzers. Most of the techniques employ ESI, every now and then MALDI, and on rare occasions I will use APCI when analyzing relatively nonpolar small molecules. For GC-MS it is almost exclusively EI with a single quad.
Q: How important is software and user interface in your MS work? How can vendors of MS or LC/GC-MS systems improve software and interface?
A: Kevin Soulsbury: BC Institute of Technology aims to introduce students to instruments, so when they enter the workplace they will understand MS workflows. In that regard, software vendors must consider the differing needs of industry and academia. For example, we need to tabulate results more easily, without setting up complicated templates.
Shaun Loeffelman: Software is very important in MS work because it processes data. Userfriendly interfaces make data processing easier. Making data output, storage, and retrieval easier and more versatile among versions of software and operating systems would help in this regard.
Suraj Saraswat: Software that is easy to use and implement is critical. Sometimes, you have to move from one vendor’s instrument to another’s. Entirely different software that is difficult to use raises concerns. Software must be self-explanatory, and interfaces should provide easy access to this software.
Chris Singleton: They are extremely important to me. I have made specific purchase recommendations based on software that was usable and easy to navigate. The software impressed me as much as the physical specs. Few things are more frustrating than a great machine hobbled by poor software. In addition, reliable batch processing takes the tedium out of data processing and instrument maintenance (tuning, calibration, etc.).
Q: Please list and explain the top two factors you consider when purchasing or specifying MS instrumentation, and explain your answers.
A: Kevin Soulsbury: A big factor is the likelihood that a student will encounter systems similar to teaching instruments when they enter industry. The other factor is local service and support. Ironically, because our instruments are not used 24/7 we tend to have more service issues than one would expect for instruments in continuous use. Local service and support help us maintain less-frequently-used equipment.
Shaun Loeffelman: Reliability and sensitivity are the top two factors I would consider when purchasing a spectrometer. Customer support and experience in the industry would also help to influence my decision in which manufacturer to choose.
Suraj Saraswat: Service is extremely important. Sometimes brand new instruments cannot be made to operate correctly. If representatives come and set up the instrument, you might need them back again sooner than expected, so they should be available for on-site or over-the-phone service whenever necessary. Also, for some reason some instruments work better for one type of application than for another. Users must therefore select instruments that best suit their application, for example, fragmentation.
Chris Singleton: Software is one factor that makes tasks easier and more efficient. Also reliability. I have used many great research-type machines in the past, but I get tired of having to fix or modify them. At this point, I want an MS that just functions reliably and is a workhorse. I can’t spare the downtime that comes from getting anything but a reliable machine.
Q: How can instrument vendors improve the MS analysis experience?
A: Kevin Soulsbury: Include more applications when instruments are introduced rather than releasing instruments without application support. Vendors should realize that the educational market is a way to introduce their brand to future users and purchasers.
Shaun Loeffelman: Vendors could offer handson demonstrations of their instruments so those in the field could get a better understanding of their instruments’ capabilities.
Suraj Saraswat: Software could be more userfriendly, with more detailed online help functions. These days, more emphasis is on sensitivity and automation with higher resolution and mass accuracy. So, it would be good if they could come up with an MS instrument with all these characteristics that is also not too expensive.
Chris Singleton: I realize it’s hard for vendors to push software, since users are more interested up front in the hard specs like resolution, mass accuracy, and linearity. But once the machine is installed, you understand the importance of software.
Our Experts: | |||
Kevin Soulsbury, Ph.D. Instructor, Department of Chemistry British Columbia Institute of Technology Burnaby, BC | Shaun Loeffelman Senior Analytical Chemist Evans Analytical Group Maryland Heights, MO | Suraj Saraswat, Ph.D. Post-doctoral Fellow Indiana University Bloomington, IN | Chris Singleton Scientist Momenta Pharmaceuticals Cambridge, MA |