大氣壓力固相、液相、及微滴游離質譜法的開發以及其在蛋白質分析上的應用

Development of Ambient Solid, Liquid, and Droplet Ionization Methods and Their Applications in Protein Analysis

謝建台(Jentaie Shiea)

《化學》 65卷2期 (2007/06) Pp. 63-69

https://doi.org/10.6623/chem.2007008

摘要

本研究開發了三種能在大氣壓力下游離蛋白質分子的新質譜游離技術(包括有大氣壓力固相游離法，大氣壓力液相游離法，以及大氣壓力微滴游離法)。這三種技術分別使用雷射脫附及霧化方式，將以固相或液相存在的蛋白質分子，導入一以有機水溶液進行電噴灑所形成的霧化區內，使其游離並產生具多價電荷之蛋白質離子。

關鍵字

大氣壓力固相游離法 ； 大氣壓力液相游離法 ； 以及大氣壓力微滴游離法 ； 雷射脫附 ； 霧化

並列摘要

As generally known, electrospraying an acidic methanol solution will produce high density of the charged species such as electron, protons, hydronium ions, methanol-water ions, cluster ions of water or methanol, and fine droplets with multi-charge on the surface. ESI plum then becomes an excellent ion source to ionize the neutral molecules that entered into the plume. By varying the method of introducing the sample into the ESI plume, unique applications were developed for solid, liquid and gas sample analyses. In this study, we introduce three hybridized methods using ESI as the post-ionization source to ionize not only small organic compounds but also large biological compounds such as proteins. The neutral molecules are introduced into the ESI plume in gaseous state through laser desorption (LD) or in the form of microdroplet through a nebulizer. ELDI (electrospray-assisted laser desorption ionization) for solid sample analysis: Solid sample placed on a sample plate were exposed to a pulsed nitrogen laser (337 nm). The laser-ablated materials were post-ionized in the electrospray solvent plume. Protein ion signals in the untreated animal's bloods, human's tear, saliva, and serum were obtained. ALMS (ambient liquid mass spectrometry) for liquid sample analysis: The sample solution mixed with μm-sized carbon powders was deposited as a droplet on a sample plate. A pulsed UV-laser was applied on droplet’s surface to desorbed analyte molecules. The desorbed molecules were post-ionized in an ESI plume. The detected protein ions remain in their native conformation. FD-ESI (fused-droplet electrospray ionizaton) for liquid sample analysis: Aerosols were generated from the aqueous sample solution with a nebulizer. Via nitrogen gas, the sample aerosols were purged into the ESI plume. The mass spectra the proteins produced in FD-ESI were predominated by the protonated molecules, and inorganic salt interference was relatively undetectable.