Alternative Carrier Gas Use for Comprehensive Two-dimensional Gas Chromatography

The vast majority of laboratories using comprehensive two-dimensional gas chromatography (GC×GC) with mass spectrometry have traditionally used helium as a carrier gas. However, the increase in ultra-high purity helium prices over the past decade and decreased availability has challenged our assumptions that helium carrier gas is a sustainable approach in the long term. This becomes even more important when performing nontargeted analysis, where all possible analytes within a sample are being targeted, and the user is relying on the inertness of the carrier gas moving the analytes through the system. This presentation will focus on the implementation of hydrogen carrier gas for GC×GC approaches and will discuss carrier gas setup options, method translation steps, as well as modulator and detector considerations for various GC×GC systems. Translated methods will be demonstrated on research applications in forensic science including fingerprint residue and organic gunshot residue profiling, also focusing on the impact of green analytical metrics used to assess instrument use. Key considerations for flow and thermal modulation will also be presented. The data demonstrates a decrease in sample run time with an increase in sample throughput, improved chromatographic resolution and run flexibility, as well as reduced reliance on high cost resources.