MALDI MS-based analysis of oligosaccharides using 4-(diphenylphosphinyl) benzenamine as non-reductive amination derivatization reagent

•Phosphoryl group has enhancement effect on MS-based oligosaccharide analysis.•4-(diphenylphosphinyl)-benzeneamine (4-DPPBA), as a novel reagent for oligosaccharides non-reductive amination derivatization, can be used for oligosaccharide analysis by mass spectrometry.•Without the tedious purification process, 4-DPPBA shows some intrinsic advantages, such as high derivatization rate, signal intensity, S/N ratio and the changeless fragment pattern between derivative and non-derivative oligosaccharide chains.

Analysis of native oligosaccharides by MS has been a challenge due in part to their limited ionization capacity. To circumvent the problem, oligosaccharides may be chemically derivatized to improve their ionization efficiency. Here, a phosphorus-containing aniline derivative, 4-(diphenylphosphinyl)-benzeneamine (4-DPPBA) was used as a reagent for oligosaccharides non-reductive amination derivatization. In general, without the tedious purification process, a significant increase about 5-fold in the mass signal intensities and 4-fold in S/N ratio were obtained. The derivatization rate is above 98% under the optimized reaction conditions. Compared with aniline, 4-DPPBA shows some merits, such as high derivatization rate, signal intensity, S/N ratio and the changeless fragment pattern between derivative and non-derivative oligosaccharide chains. Based on the advantages, 4-DPPBA is of great potential to be one kind of oligosaccharides derivatization reagent with high performance and widely used in the analysis of oligosaccharides.

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