Analysis of the glucosinolate pattern of Arabidopsis thaliana seeds by capillary zone electrophoresis coupled to electrospray ionization-mass spectrometry.

An easy and rapid method for the analysis of intact, non-desulfated glucosinolates by capillary zone electrophoresis (CZE) coupled to electrospray ionization-time of flight-mass spectrometry (ESI-TOF-MS) is described. Surprisingly, an electrolyte and a sheath liquid based on formic acid provided the best results. In this strongly acidic system, the glucosinolates were separated and detected as anions, resulting in an excellent selectivity. Thus, crude plant extracts could be analyzed without any interference of matrix constituents. The sensitivity together with mass accuracy and true isotopic pattern of the TOF-MS allowed identification of a broad series of glucosinolates in Arabidopsis thaliana seeds.