Fixed-charge generation derivatization for analysis of thiols by «soft» ionization mass spectrometry methods
T16N1
A.V. Kozlov, R.S. Borisov, V.G. Zaikin
A new method for the fixed-charge generation derivatization of thiols of different structures by reaction with haloalkanes and dibromides was suggested. It was shown that 1,4-dibromobutane and 1,2-xylylene dibromide are the most effective alkylating agents, that provided the formation of stable five-membered ring with a positively charged sulfur atom. Such cations are readily detected by electrospray ionization and matrix-assisted laser desorption/ionization mass spectrometry methods. Sulfonium cations were further studied by tandem mass spectrometry using collision-induced dissociation (CID). Typical and specific directions of CID for cyclic cations formed from thiols of different structures were established. They can be used to identify and quantify the thiol analytes by the selected reaction monitoring method.