庆大霉素的电喷雾质谱分析

Electrospray Ionization Mass Spectrometry of Gentamicin

目的应用电喷雾离子化串联质谱探讨庆大霉素的质谱断裂规律。方法在正离子检测模式下,以电喷雾离子化法对庆大霉素进行多级质谱分析。结果在二级质谱分析中,庆大霉素中的各化合物均发生B环和C环间的糖苷键断裂,生成脱去C环(氨基葡萄糖)的二级碎片离子m/z322.0,再对m/z322.0进行分析时,生成分别脱A环(氨基葡萄糖)或B环(脱氧链霉胺)的碎片离子m/z163.0或m/z160.0。结论通过对庆大霉素的电喷雾质谱的分析,丰富了其分子结构信息,并可用于该类化合物的结构快速鉴定和定量分析。

Objective To study the electrospray ionization （ESI） mass spectrometry of gentamicin. Methods The ESI source was set at the positive ionization mode, and the MSn spectra of gentamicin were acquired. Results The abundant product ion was m/z322.0 by loss of the C-ring （amino-α-D-glucopyranose） in MS2 full scan mode of gentamicin. In MS2 full scan mode of m/z322. 0, the prominent fragmentation ions were at m/z163.0 and m/z160.0 by loss of the A-ring （amino-α-D-glueopyranose） and B-ring （2-deoxy- D-streptamine） , respectively. Conclusion The structural information of gentamicin was obtained via collision-activated dissociation and these characteristics are applicable to the structural elucidation and quantitative analysis of gentamicin.