Analysis of water-soluble vitamins by high-performance liquid chromatography–particle beam-mass spectrometry

Abstract

Particle beam (PB) LC–MS was investigated for the analysis of eleven water-soluble vitamins. A reversed-phase chromatographic method making use of volatile buffers was set up for the simultaneous separation of this mixture by using narrow-bore columns. After optimization of the PB interface parameters, the effect of the MS source temperature was evaluated at 200 °C and 300 °C in electron impact (EI) and chemical ionization (positive-ion, PCI and negative-ion, NCI) modes. Electron impact mass spectra were library-searchable, but generally sensitivity was better under PCI conditions. Under these conditions and operating in selected-ion monitoring mode, linearity, detection limits and precision of the analysis was explored. Detection limits at the low-ng level were achieved for nicotinamide, nicotinic acid in PCI mode and pyridoxal under NCI conditions; repeatability of <6%(RSD) was obtained for all the compounds examined except for biotin.