Technology Forum: GC

From environmental research to petroleum research to testing blood for doping agents, GC remains a workhorse in the field of chromatography. And though other techniques are challenging GC and seeking to dethrone it, none have been completely successful to this point, as GC promises to remain relevant for years to come.

Joining us for this discussion are Sky Countryman of Phenomenex; Nicholas H. Snow of Seton Hall University; and Michael Feeney of Agilent Technologies, Inc.

What trends have you most intrigued in the GC field?

Countryman:GC analysis is getting much more demanding: faster analysis, more sensitivity, better stability, while including a broader range of compounds. For example, the EPA is updating methods like 8270 and 8260 to include more compounds and more stringent quality control measures. In response, system and column manufacturers are pushing the limits of their respective technologies in order to give chromatographers specialized solutions.

Snow: I am most intrigued by the continuing development and simplification of previously very complex and challenging instrumentation. On-line and automated sample preparation, GC–MS, GCxGC, GCxGC-TOF-MS, and complex switching valves are now routinely available off the shelf, often from multiple vendors. In many ways, a GC–MS is now simpler to set up, operate, and maintain than a GC-FID. The other important trend is that these more complex techniques are rapidly leaving the realm of chromatography researchers and entering the more mainstream scientific community. I see these new capabilities as a renaissance in GC. It’s not your father’s old packed columns anymore.

Feeney: The average experience level for GC and GC–MS operators has been decreasing for over a decade and this provides challenges to lab managers and instrument manufactures alike. Companies are looking for reliable, easy to maintain and operate systems, which provide many years of useful lifetime. Instrument manufacturers need to respond by developing new hardware and software that best meet these needs of their customers.

Are you expecting any new developments at Pittcon 2009?

Countryman:I expect to see companies providing more specialized solutions for popular applications, such as food safety and residual solvents. I also expect these to be much more comprehensive solutions providing everything from sample preparation to sample analysis. Labs are looking for turnkey solutions that can be implemented immediately.

Snow:As has been the case over the past several years, this year’s Pittcon will see incremental improvements in instrumentation from the vendors, with more vendors offering complex pneumatics, instrument control and configuration options, and data analysis capabilities. Pittcon still provides the best opportunity to comparison shop between the numerous available options. In the technical program, I expect to find growing applications for GC. However, conferees may have to do some hunting to find them; they will be in sessions on food science, product safety, environmental analysis, and other application areas that do not necessarily have GC in the title.

Feeney:I have heard that my company will have a new automatic liquid sampler for their GC products. In addition to increasing the number of sample vials for high productivity laboratories, this sample provides optional heating, mixing, and liquid addition to automate many common sample preparation steps that GC operators currently have to do manually.

What is the GC application area that you see growing the fastest?

Countryman:I see the biggest growth for GC in the area of food safety testing. Worldwide concern resulting from a second melamine outbreak has again put the spotlight on food quality. The sheer number of compounds and the complexity of the sample matrix require very robust analytical procedures. GC plays a key role in the analysis of these food contaminants.

Snow:As has also been the trend over the past several years, applications related to public and product safety are at the forefront of analytical chemistry and gas chromatography in particular. We will see growth and new applications in environmental, food and pharmaceutical analysis, and in product safety. The use of GC in many quality assurance applications could use a makeover with the new capabilities now available in automated on-line sample preparation, multidimensional separations, and mass selective detection.

Feeney:Food safety and quality analyses are the fastest growing application area in many parts of the world today. GC with selective detection and GC–MS provide capabilities to analyze many pesticides and other regulated organic compounds that are being detected in food.

What obstacles stand in the way of GC development?

Countryman:The use of GC is limited by the number of compounds that can be analyzed by this technique. More and more labs are converting methods to LC or LC–MS in order to eliminate sample preparation steps or to improve sensitivity. As the price of the LC systems decreases, we expect to see more methods move away from GC. In order to counteract this, GC companies must continue to develop solutions that simplify the overall analysis. Along these lines, our company has been developing specialized GC phases that improve the analysis of key applications such as biofuels, drugs of abuse, and environmental samples.

Snow:Today’s biggest obstacle in GC is the same as for R+D in general: the economy causing shrinking budgets for research and capital expenses. However, I encourage laboratories with tight budgets to consider giving GC another look. Gas chromatography and GC–MS provide among the best and most cost-effective means for laboratories to obtain versatile, highly capable instrumentation, especially for trace analysis. The other obstacle remains the perception, left over from packed column days, of GC as a technique only for obviously volatile compounds. We still have not fully exploited GC’s capability to analyze semi-volatile analytes. For instance, in mainstream analysis, we have never really taken advantage of cool on-column and programmed temperature vaporization inlets, which mitigate many of difficulties with hot injections of labile compounds. Further, much of the coverage of gas chromatography in undergraduate curricula is still too firmly rooted in older packed column ideas.

Feeney:The current worldwide economic situation raises concerns that companies will not have the financial resources to replace aging equipment or upgrade to new equipment, which increases laboratory productivity.

What was the biggest accomplishment or news in 2008 for GC?

Countryman:With capital budgets being reduced, most labs do not have the luxury of getting the latest and greatest system. We have been focused on developing GC column solutions that improve analysis on any GC or GC–MS system. Our specialized solutions for drugs of abuse, blood alcohols, and biofuels have given all labs the ability to improve their productivity without making a large capital investment. We feel this will become increasingly important over the next several years.

Snow:It is difficult to point to a single 2008 news item, but the trends we have been discussing are news in itself. Today’s GC is not the same old mature technique; it is young, fresh, and dynamic. We are finally able to fully utilize all of the separation power that capillary columns provide, along with selective detectors and automated analysis. Every analyst who has used GC over the past generation needs to take a close look at these new systems, applications, and capabilities.

Feeney:My company's acquisition of RVM Scientific, a small company that developed a unique way to rapidly heat and cool GC columns was a significant development. This column heating/cooling technology offers the ability to decrease cycle times in GC analysis by a factor of 5 to 10 times for many applications.