From Gas to Gas: Fundamentals of Static Headspace Extraction-Gas Chromatography

Abstract

Headspace sampling is one of the staple sample introduction techniques for gas chromatography (GC) because it involves the injection of samples already in the vapor phase into the instrument. In this installment, we discuss the fundamentals of headspace extraction, including static versus dynamic extraction, establishing equilibrium in the vial, consequences of the partition coefficient, temperature, pressure, and transfer to the gas chromatograph. We see how, with consideration of the fundamental chemical equilibria involved, headspace extraction with GC can be one of the simplest yet most powerful and versatile chromatographic techniques.