The purpose of derivatisation
In gas chromatography it is often advantageous to derivatise polar functional groups (mainly active hydrogen atoms) with suitable reagents. Prerequisite for successful derivatisation is quantitative, rapid and reproducible formation of only one derivative. Aim of this reaction is an improved volatility, better thermal stability or a lower limit of detection due to improved peak symmetry. The halogen atoms introduced by derivatisation (e.g. trifluoroacetates) allow specific detection (ECD) with the advantage of high sensitivity. Elution orders and fragmentation patterns in mass spectroscopy can be influenced by a specific derivatisation.
If you are in doubt which type of derivatisation reaction best suits your needs, or which reagent is best suited for your sample, you can try different methods or different reagents by using the derivatisation method development kits.
We supply the following derivatisation reagents for silylation, acylation, and alkylation (methylation):
Reagents for silylation
Additionally, we supply some mixtures of silylation reagents with or without pyridine.
Reagents for acylation
HFBA heptafluorobutyric acid anhydride
PFBC pentafluorobenzoyl chloride
TFAA trifluoroacetic acid
Reagents for methylation
TMSH trimethylsulfonium hydroxide (in methanol)