YL INSTRUMENT GAS CHROMATOGRAPHS
A gas chromatograph (GC) is an analytical instrument that measures the content of various components in a sample.
The principle of gas chromatography are as follows:
- The sample solution is injected into the instrument and enters a gas stream which transports the sample into a separation tube known as the "column." (Note: Helium or nitrogen is used as the so-called carrier gas).
- The various components are separated inside the column.
- The detector measures the quantity of the components that exit the column.
- In order to measure a sample with an unknown concentration, a standard sample with a known concentration must first be injected into the instrument. The standard sample peak retention time (appearance time) and area are compared to the test sample to calculate the concentration.