Separation, detection, identification, and quantification—these steps form the basis of purity analysis with low detection limits, which is a typical workflow of GC-MS. Gas chromatography–mass spectrometry (GC-MS) is particularly well-suited for the analysis of volatile and semi-volatile compounds, including a wide variety of organic molecules such as alcohols, esters, nitro compounds, long-chain hydrocarbons, organic acids, steroids, and alkaloids.