高灵敏度纳喷雾正交飞行时间质谱法

High Sensitivity Nanoelectrospray Ionization Orthogonal Injection Time-of-flight Mass Spectrometry

研制了纳喷雾离子化技术与正交飞行时间质谱的联用接口 ,在电场力的作用下 ,样品流速约为 30nL/min ,4 0nmol/L细胞色素c溶液的单张图谱样品消耗量为 0 0 2amol、检测限约为 0 8～ 1 2zmol.由于纳喷雾离子化技术的离子化机理与常规离子化方法有所不同 ,由母液滴裂解成能被直接检测的液滴的步骤少 ,因此能增加检测的灵敏度 ,特别适合于分析多糖类分子 .通过分析SBE β CD获得了较满意的结果 .另外还分别对agiotensinⅠ进行了源内CID实验和对细胞色素c的胰酶酶解图谱进行分析 ,对所有酶解的多肽混合物离子作了归属 .证明纳喷雾技术是一种高灵敏度 ,且适合于分析复杂基质环境及微量样品的技术 .

A nanoelectrospray interface was set up for hyphenating with orthogonal injection time of flight mass spectrometer. Low detection limit (about 0 8～1 2 zmol) and low sample consumption (about 0 02 amol) per spectrum was obtained by injecting horse heart cytochrome c into the mass sepectrometer with a nanoelectrospray interface at a flow rate of 30 nL/min. As smaller droplet is formed in nanoelectrospray process, the desolvation efficiency and the ionization efficiency could be enhanced and thus may facilitate analysis of oligosaccharides. A better signal was obtained in analyzing SBE β CD by the nanoelectrospray interface compared with a microspray interface. In addtion, in source CID experiment of agiotensin Ⅰ and trypsin enzymatic peptides map of cytochrome c were achieved by nanoelectrospray interface, respectively. The results showed that all but one ion in cytochrome c was achieved clearly in nanoelectrospray spectrum.