Department of Chemistry, Sejong University, 98 Gunja-dong, Gwangjin-gu, Seoul 143-747, Republic of Korea.
Carbohydr Res. 2010 Feb 11;345(3):408-13. doi: 10.1016/j.carres.2009.11.028. Epub 2009 Nov 26.
Glucose, galactose, and mannose in H(2)O and D(2)O were ionized by an atmospheric pressure chemical ionization (APCI) method. Isotope effects on fragmentation patterns of the monosaccharides were examined by deuterium replacement of the -OH groups to distinguish the isomers with a single mass spectrometer. The most abundant ions were the M+H(2)O() and M(D5)+D+D(2)O for using H(2)O and D(2)O as solvent and eluent, respectively. Major fragment ions were the M-OH and M-OH-H(2)O in H(2)O, while those in D(2)O were the M(D5)+D-D(2)O and M(D5)+D-2D(2)O. The differences in the product ions generated in H(2)O and D(2)O were due to enhancement of the strength of hydrogen bonding by the deuterium replacement. Variations of the ion intensity ratios of the M-OH/M-OH-H(2)O and M(D5)-OD/M(D5)-OD-D(2)O with the fragmentor voltage showed different trends depending on the kind of monosaccharides. By comparing the ion intensity ratios of the M+H(2)O()/M(+)(), M(D5)+D+D(2)O/M(D5)+D, M-OH/M-OH-H(2)O, and M(D5)+D-D(2)O/M(D5)+D-2D(2)O, it was possible to distinguish the isomers of monosaccharides.
在 H(2)O 和 D(2)O 中，葡萄糖、半乳糖和甘露糖通过大气压化学电离 (APCI) 方法进行离子化。通过 -OH 基团的氘取代来检查单糖的碎裂模式的同位素效应，以使用单一质谱仪区分异构体。最丰富的离子是 M+H(2)O() 和 M(D5)+D+D(2)O，分别使用 H(2)O 和 D(2)O 作为溶剂和洗脱液。在 H(2)O 中，主要的碎片离子是 M-OH 和 M-OH-H(2)O，而在 D(2)O 中，产物离子是 M(D5)+D-D(2)O 和 M(D5)+D-2D(2)O。在 H(2)O 和 D(2)O 中生成的产物离子的差异是由于氘取代增强了氢键的强度。M-OH/M-OH-H(2)O 和 M(D5)-OD/M(D5)-OD-D(2)O 的离子强度比随碎片电压的变化因单糖的种类而异。通过比较 M+H(2)O()/M(+)()、M(D5)+D+D(2)O/M(D5)+D、M-OH/M-OH-H(2)O 和 M(D5)+D-D(2)O/M(D5)+D-2D(2)O 的离子强度比，可以区分单糖的异构体。
