Retensjonsindekser

Retensjonsindekser, also known as retention indices, are numerical values used in gas chromatography (GC) to identify and quantify compounds in a sample. They are calculated based on the retention time of a compound relative to a set of reference compounds with known retention times. The retention index (RI) is a dimensionless number that provides a more consistent and reproducible way to identify compounds compared to retention times alone, which can vary due to changes in column temperature, flow rate, and other factors.

The calculation of retention indices involves the use of a set of reference compounds, typically n-alkanes, which are injected into the GC system along with the sample. The retention time of each reference compound is measured, and a plot of retention time versus carbon number is generated. The retention index of an unknown compound is then determined by interpolating its retention time on this plot.

Retensjonsindekser are widely used in various fields, including environmental analysis, food science, and pharmaceuticals, to identify and quantify compounds in complex mixtures. They provide a valuable tool for compound identification and can be used in conjunction with other analytical techniques, such as mass spectrometry, to confirm the identity of compounds in a sample.