1.1. Overview of GC Analysis
Gas chromatography (GC) is an analytical technique applicable to gas, liquid, and solid samples (components that are vaporized by heat). If a mixture of compounds is analyzed using GC system, each compound can be separated and quantified.
When a mixed solution sample is injected into the GC system, the compounds contained in the sample, including the solvent components, are heated and vaporized within the sample injection unit.
With GC system, the mobile phase, referred to as the carrier gas, always flows in sequence from the sample injection unit to the column, and then to the detector. The target components that were vaporized in the sample injection unit are transported by the carrier gas to the column. Once in the column, the mixture of compounds is separated into the various components, and the amount of each compound is then measured by the detector.
The detector converts the amount of each compound into an electrical signal, and sends these signals to a data processing unit. The data obtained enables determination of the compounds contained in the sample, and in what amounts.