Eric Denoyer, PhD, (left) is the senior marketing director of the Gas Phase Solution Division at Agilent Technologies. He has been developing gas chromatography (GC) and mass spectrometry (MS) instrumentation over the last 15 and 18 years, respectively. During that time, Denoyer has also been responsible for developing software systems to support that instrumentation.

Joe Hedrick (right) is the outbound marketing manager of the Gas Phase Solution Division at Agilent Technologies. He has been with Agilent for almost 30 years, most of that time as a field application chemist, teaching and consulting on GC and GC-MS. Part of his team in his current role includes a group of chemists in Wilmington, Delaware, US; and Shanghai, China, that develop new gas phase applications as well as optimize older applications to take advantage of newer technology and techniques.

Q: What applications/research fields are best suited for the use of gas chromatography methods?

Joe Hedrick: GC and GC-MS have become fundamental tools in nearly all scientific, industrial, and regulatory fields. Gas chromatography is best suited for the analysis of complex mixtures or target analysis of specific analytes in complex mixtures. As the name implies, it is applicable to any material or analyte that has a significant vapor pressure and is stable at elevated temperatures.

Q: Are there any new applications where GC is emerging as a useful technique?

Joe Hedrick: Gas chromatography applications are constantly growing as scientific fields expand, new materials are discovered, and the importance of different biologic pathways are explored. The basic use of gas chromatography, the quantitative and qualitative analysis of complex mixtures, has remained relatively constant. How and what that “use” is applied to continues to evolve. Metabolomic analysis in breath, biomarkers in crude oil, identifications of cannabinoids in hemp extracts, to name a few. The list of new applications of an “old” tool is long and growing.

Q: How have GC instruments evolved in recent years? How do you anticipate they will continue to adapt or change in the future?

Eric Denoyer: GC is a mature technology, so while incremental performance and quality improvements have indeed been made over recent years, the major breakthroughs in GC development have involved the user experience. Specifically, GC systems have become smarter with more powerful automated troubleshooting and diagnostic functions. They are supported by much more intuitive user interfaces and consumables, so they are easier to use and operators can achieve better results faster, with fewer mistakes.

GCs are also becoming more connected and many are now designed as internet appliances. As such, they can be connected to by mobile devices such as tablets or phones, so managers and operators can view status, troubleshoot, and control operations remotely. Further development of these smart connected IoT (internet of things) functions is a major future trend for GC (and other analytical instrumentation) in the future.

Q: What are the most common challenges users of GC face?

Joe Hedrick: The most common challenges we hear are not directly related to GC but on either side of the GC analysis. Sample preparation continues to be a challenge, especially with lower detection limits, sample tracking becomes more challenging as sample load increases, and along with that interpreting and reporting of results. Gas chromatographs continue to evolve and are becoming easier to use and more reliable, which is leading to higher sample loads. The higher sample loads in turn put pressure on other parts of the sample analysis chain.

Q: What sort of obstacles arise when developing new, innovative GC instrumentation?

Eric Denoyer: All new technologies face adoption challenges, especially when replacing established mature technologies. Making sure the new technology is amenable to specific applications can take time and everyone is busy. The more new, innovative GC instrumentation gets out there and proves its value, the more adoption will occur—it will build on itself.

Developing new, innovative GC instrumentation can be a challenge, and seeking end user input isn’t always easy. Henry Ford said if you asked customers what they wanted in new transportation, they would have said a faster horse. That’s because it is not always evident to end users what might even be possible. They usually don’t have access to the high-end R&D teams who are dreaming up innovative new approaches that instrument manufacturers do. So, voice of customer usually focuses on what “needs” to be accomplished rather than on “how” it should be accomplished. And if the “how” ends up being significantly different than the established norm, it can be a surprise and potentially of concern to the end user. That’s why the benefits of new, innovative instrumentation must be made very clear at the outset, to overcome this possible obstacle to adoption.

Q: How has automation played a role in GC development?

Eric Denoyer: Over the past 50 years, more and more processes have become automated in GC. Automation doesn’t necessarily replace operators, but instead frees them up for other more value-added activities. One of the earliest and arguably one of the most impactful was automatic integration of GC peaks. Cutting and weighing GC peaks is difficult to imagine these days, especially for younger users, but for some it was real, and a real time sink as well.

Automated sample injection was another major leap forward. It not only untethered operators from the instrument, but also led to a much higher degree of precision and reproducibility. Surprisingly, it took decades to become fully accepted, but is de rigueur these days.

Probably the next big leap in automation is within the digital domain. Automated troubleshooting and diagnostics are now a reality and greatly reducing maintenance downtime. Automated system performance and status checks assure systems are fit and configured for purpose. This is not only important for streamlining quality control, but also for documentation in regulated environments, or in expert testimony. Automation in data analysis and review is a holy grail that is also being addressed, to help to reduce what many lab managers consider their greatest productivity bottleneck.

Q: Any advice for choosing the right GC equipment for a specific application, or any maintenance tips to keep equipment running efficiently?

Eric Denoyer: One of the best words of advice for keeping a GC up and running at its very best is to carry out regular preventive maintenance. While some lab managers fear this could increase running costs, it saves costs by reducing unplanned downtime. Many modern GCs are equipped with early maintenance feedback systems and can alert users as the time for maintenance approaches. Having a liner or a septum reach the end of its useful life in the middle of a batch run is frustrating at best. It can not only result in sample reruns, increasing cost and decreasing productivity, it can also result in the loss of precious sample which may be irreplaceable.

GCs can be configured in so many different ways to do so many different things. But there are many resources available to help choose the right GC. First, application notes from GC vendors are widely available and can identify the right configuration for the job. Online communities that some GC vendors host also can provide peer-to-peer advice that can be trusted to help in the decision process. Finally, most vendors have sales and support teams that are expertly trained and ready to provide professional advice on instrument configurations for different applications. In fact, one of the best resources for discussing the right GC for you is the service engineer visiting the lab for maintenance or repair on your existing GC.