Ramos, Susana SofiaRamalho, LuísCosta, MafaldaTeixeira, AdrianoAlmeida, PauloCosta, Maria do Céu2010-06-222010-06-222007Ramos, Susana Sofia; Ramalho, Luís; Costa, Mafalda; Teixeira, Adriano; Costa, Maria do Céu; Almeida, Paulo. Mass spectrometric analysis of epimeric 3α/3β functionalized steroids. In: ARKIVOC, 2007, vol. xiv, p. 163-171http://hdl.handle.net/10400.9/695Tandem mass spectrometry (MS/MS) using an atmospheric pressure chemical ionization (APCI) source in positive mode (+) reveals different intensity ratios of two fragment peaks of the epimeric cholestane derivatives synthesized from 3{460}- or 3β-cholestanol. The investigation of the fragmentation pattern obtained from their full scan and/or collision induced dissociation (CID) spectra in the case of the cholestane skeleton together with the respective electronic ionization (EI) spectra supports a distinction of the epimers.engAPCIEITandem MSEpimer discriminationjournal article