红外和CD光谱的HSA糖基化反应产物结构和反应进程分析

用干法制备糖基化产物。人血清白蛋白(HSA)与葡萄糖质量比1∶1，溶解混和均匀，经48 h冷冻干燥，根据不同反应时间得到20个样本。旨在联合多光谱学技术(紫外、荧光、近红外、红外和圆二色光谱(CD光谱))分析人血清白蛋白糖基化前后二级三级结构和官能团的变化信息，以及分析不同反应时间对HSA糖基化产物结构特性的影响。实验结果表明：HSA与葡萄糖在干热条件下极易发生糖基化反应；随反应时间延长，蛋白质紫外吸收强度减弱，内源荧光吸收强度增强，糖基化反应增强，美拉德反应程度提高，蛋白质二级三级结构相应发生变化。反应到140 min左右时，美拉德反应前期糖基化反应完全，生成Amadori产物，进一步加热反应到220 min左右，反应进入中后期，开始生成醛酮类物质，反应到280 min左右，蛋白质氨基酸与羰基化合物发生脱羧、脱氨反应。

Research in Glycated Progress and Products of Human Serum Albumin by Infrared and CD Spectroscopy

In this study, human serum albumin (HSA) glycated products in dry processing, HSA and glucose were mixed into solution with mass proportion of 1∶1, free-drying for 48 h, totally 20 samples were obtained according to different reaction times. This study mainly used multi-spectral technology (UV, fluorescence, near infrared spectroscopy, infrared spectroscopy, CD spectroscopy) to analyze the changes of protein secondary tertiary structure, functional groups after glycation of HSA, glycated product and progress of protein. The results show that, the glycation process is easy to occur when HSA was mixed with the glucose in hot and dry conditions, with the increase of reaction time, UV absorption intensity weakened, fluorescence absorption intensity increased and reveal the higher degree of glycation and Maillard reaction, the secondary tertiary structure of protein had small changes. The reaction took about 140 min, the glycation was complete, the Amadori product was formed, and then was further heated to about 240 min, the reaction entered the middle and late period, and the aldehydes and ketones were formed. The reaction took about 280 min, protein amino groups and carbonyl compounds occurred decarboxylation and deamination.