Abstract
Thermospray liquid chromatography/mass spectrometry with a new, strongly acidic mobile phase, i.e., formic acid-ammonium formate buffer system, was applied to the analysis of five kinds of water-soluble vitamins. Their detection limits, linearity and reproducibilities were examined. The mass spectra of the individual vitamins gave MH+ ions; some of these showed fragment ions giving information on molecular structure. Detection limits (S/N)>10) were 10-100pg; reproducibility of 1.2-4.9% (RSD) was obtained for 10μl syringe injections, based on peak areas. The water-soluble vitamins in a commercial health drink and in fermented soybean paste miso were determined by this method.
