Carbohydrate Analysis in Fermentation Samples by Reversed-Phase Liquid Chromatography with Mass Spectrometry Detection Using Precolumn Derivatization with Dibenzylamine

Liquid chromatography–mass spectrometry (LC–MS) technique has been widely used for the determination of trace carbohydrate compounds in biological samples. However, the ionization efficiency of carbohydrates under the conditions of common electrospray ion sources is poor, and thus chemical derivatization treatment is usually needed. Here, a pre-column derivatization based on dibenzylamine method coupling with LC–MS/MS was developed for the analysis of glucose, xylose, ribose, galactose, maltose, and maltotriose. Aldosaccharide compounds were labeled by dibenzylamine within 3 h at 75 °C. The derivatized aldosaccharides were separated on a polar-copolymerized C18 column and identified with electrospray ionization mass spectrometer in positive mode. The dibenzylamine-derived product of 3-O-methyl-D-glucopyranose was used as the internal standard for the quantitation of derivatized aldosaccharide products. Under the optimized condition, good correlation coefficients ( R 2 > 0.9903) for all carbohydrates were obtained. Outstanding sensitivity with limits of quantitation (S/N 10) of 0.35–20 ng mL −1 and limits of detection (S/N 3) of 0.1–7 ng mL −1 were achieved. The developed method was successfully utilized for the determination of aldosaccharides in sample of corn stalk fermentation. The recoveries of the method were in the range of 92.59–103.22% with relative standard deviations of 1.08–6.08%.