Rapid identification and quantitation of protein by using mass spectrometry

以蓖麻毒素和牛酪蛋白为模型蛋白，通过液相色谱/质谱（LC/MS）或基质辅助激光解吸电离（飞行时间）/质谱（MALDI-TOF/MS）进行胰蛋白酶消化和多肽鉴定。选择用于鉴定每种蛋白的标记肽。以蓖麻毒素为研究对象，建立了基于乳糖亲和的蓖麻毒素提取方法。将乳糖固定在单片二氧化硅上，作为捕获配体从样品溶液中提取蓖麻毒素，二氧化硅被支撑在圆盘填充的旋转柱中。从粗样品中提取、检测和鉴定蓖麻毒素，整个过程耗时约5小时。

Ricin and bovine casein were used as model proteins for tryptic digestion and peptide identification by liquid chromatography/mass spectrometry(LC/MS) or matrix-assisted laser desorption ionization-(time-of-flight)/MS(MALDI-TOF/MS). Marker peptides for identification of each protein were selected. In case of ricin, extraction method based on lactose affinity was developed as a method for rapid and accurate determination of ricin. Lactose was immobilized on monolithic silica, was used as a capture ligand for ricin extraction from the sample solution, and the silica was supported in a disk-packed spin column. It took approximately 5 h to carry out the entire procedure through extraction, detection and identification of ricin from crude samples.