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
BSA               N,O-bis-trimethylsilyl-acetamide
BSTFA            N,O-bis-trimethylsilyl-trifluoroacetamide
DMCS            dimethylchlorosilane
HMDS            hexamethyldisilazane
MSHFBA         N-methyl-N-trimethylsilyl-heptafluorobutyramide
MSTFA           N-methyl-N-trimethylsilyl-trifluoroacetamide
MBDSTFA       N-methyl-N-tert-butyldimethylsilyl-trifluoroacetamide
TMCS            trimethylchlorosilane
TSIM             N-trimethylsilyl-imidazole

Additionally, we supply some mixtures of silylation reagents with or without pyridine.

Reagents for acylation
HFBA            heptafluorobutyric acid anhydride
MBTFA          N-methyl-bis(trifluoroacetamide)
MBHFBA        N-methyl-bis(heptafluorobutyramide)
PFBC            pentafluorobenzoyl chloride
TFAA            trifluoroacetic acid

Reagents for methylation
DMF-DMA      N,N-dimethylformamide-dimethylacetal
TMSH           trimethylsulfonium hydroxide (in methanol)