Axial thermal gradients in microchip gas chromatography

作者：Wang Anzi; Hynynen Sampo; Hawkins Aaron R; Tolley Samuel E; Tolley H Dennis; Lee Milton L^*

来源：Journal of Chromatography A, 2014, 1374: 216-223.

DOI：10.1016/j.chroma.2014.11.035

• Gas chromatography
• Microfabrication
• Thermal gradient
• Peak focusing
• Resolution

Fabrication technologies for microelectromechanical systems (MEMS) allow miniaturization of conventional benchtop gas chromatography (GC) to portable, palm-sized microfabricated GC (mu GC) devices, which are suitable for on-site chemical analysis and remote sensing. The separation performance of mu GC systems, however, has not been on par with conventional GC. Column efficiency, peak symmetry and resolution are often compromised by column defects and non-ideal injections. The relatively low performance of mu GC devices has impeded their further commercialization and broader application. In this work, the separation performance of mu GC columns was improved by incorporating thermal gradient gas chromatography (TGGC). The analysis time was similar to 20% shorter for TGGC separations compared to conventional temperature-programmed GC (TPGC) when a wide sample band was introduced into the column. Up to 50% reduction in peak tailing was observed for polar analytes, which improved their resolution. The signal-to-noise ratios (S/N) of late-eluting peaks were increased by 3-4 fold. The unique focusing effect of TGGC overcomes many of the previous shortcomings inherent in mu GC analyses.

• 出版日期2014-12-29