Miniaturized systems for gas chromatography: Developments in sample preparation and instrumentation.

An important field of research is the miniaturization of analytical systems for laboratory applications and on-field analysis. In particular, gas chromatography (GC) has benefited from the recent advances in enabling technologies like photolithography, micromachining, hot embossing, and 3D-printing to improve sampling and sample preparation, microcolumn technologies, and detection. In this article, the developments and applications reported since 2015 were reviewed and summarized.

Practical Considerations in Method Development for Gas Chromatography-Based Metabolomic Profiling.

This chapter discusses the fundamentals of gas chromatography (GC) to improve method development for metabolic profiling of complex biological samples. The selection of column geometry and phase ratio impacts analyte mass transfer, which must be carefully optimized for fast analysis. Stationary phase selection is critical to obtain baseline resolution of critical pairs, but such selection must consider important aspects of metabolomic protocols, such as derivatization and dependence of analyte identification on existing databases.

Electromembrane extraction and preconcentration of carbendazim and thiabendazole in water samples before capillary electrophoresis analysis.

Electromembrane extraction using a polypropylene hollow fiber impregnated with 1-ethyl-2-nitrobenzene was evaluated for the extraction and preconcentration of the fungicides thiabendazole and carbendazim from water samples before capillary electrophoresis analysis. The composition of the supported liquid membrane, the HCl concentration in the acceptor solution, and the stirring rate (of the donor solution) were optimized using the one-variable-at-a-time method. In contrast, a face-centered central composition design was used for optimization of voltage, extraction time, and concentration of HCl in the donor solution.