Burlingame A L
Department of Pharmaceutical Chemistry and the Liver Center, University of California, San Francisco 94143-0446, USA.
Curr Opin Biotechnol. 1996 Feb;7(1):4-10. doi: 10.1016/s0958-1669(96)80088-7.
Electrospray ionization, a natural interface with microbore and capillary high-pressure liquid chromatography, has become the method of choice for the reliable structural characterization of protein glycosylation by mass spectrometry at the picomole level. Its advantages include inherent sensitivity in the femtomole range, compatibility with collisional activation methods that both permit the detection and monitoring of structurally specific ions and enable the induction of glycopeptide fragmentation that facilitates determination of glycoform sequence and branching. Developments in high-performance electrospray mass spectrometry include sample introduction at nanoliter flow rates, tandem magnetic sector/orthogonal time-of-flight instruments, Fourier transform instruments, and new ion optical strategies, including ion traps. Although a sensitive and important complementary technique, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry suffers from matrix-dependent deposition of excess internal energies, which produce extensive metastable fragmentation and (photo)adduct formation. These metastable fragments may be focused into a mass spectrum by employing an ion mirror (reflectron) in time-of-flight instrumentation. In favorable cases, structural information may be obtained.
电喷雾电离作为一种与微径和毛细管高压液相色谱的天然接口，已成为通过质谱在皮摩尔水平可靠表征蛋白质糖基化结构的首选方法。其优点包括在飞摩尔范围内固有的灵敏度，与碰撞激活方法的兼容性，这既允许检测和监测结构特异性离子，又能诱导糖肽断裂，从而有助于确定糖型序列和分支。高性能电喷雾质谱的发展包括纳升流速进样、串联磁扇区/正交飞行时间仪器、傅里叶变换仪器以及新的离子光学策略，包括离子阱。尽管基质辅助激光解吸/电离飞行时间质谱是一种灵敏且重要的补充技术，但它存在基质依赖的过量内能沉积问题，这会产生广泛的亚稳裂解和（光）加合物形成。通过在飞行时间仪器中使用离子镜（反射器），这些亚稳碎片可能会聚焦到质谱图中。在有利的情况下，可以获得结构信息。
