Hyphenated liquid chromatography–gas chromatography technique: Recent evolution and applications

Liquid chromatography (LC) hyphenated with gas chromatography (GC) was first presented in 1979. Since then an intensive study has been carried out to explore different types of interfaces both for coupling normal-phase (NP) and reverse-phase (RP) LC with GC. The present review focuses on the technical progress and applications presented in the last decade, and it describes the most used interfaces. In fact, more flexible interfaces have been studied to improve the use of LC–GC, in particular the use of a programmed temperature vaporizer (PTV) injector. An intensive effort has also been devoted to optimizing the coupling of reverse-phase LC for analysis of water-based samples. A brief overview of comprehensive approaches (LC × GC) is discussed along with perspective for further improvement of the technique.