中文摘要：

利用双偏振极化干涉测量仪（DPI）研究了界面上配基种类对BSA吸附行为的影响。采用3-氨基丙基三乙氧基硅烷（APTES）、3-（甲氨基）丙基三甲氧基硅烷（MAPTMS）和N，N-二乙基-3-氨基丙基三甲氧基硅烷（DAFFMS）对DPI芯片进行了修饰，利用X射线光电子能谱比较了芯片上不同配基的密度，采用原子力显微镜（AFM）和DPI对界面上BSA吸附行为进行了研究。结果表明APTES修饰界面上BSA呈饼状，高配基密度易导致BSA多位点吸附。相同偶联密度条件下BSA在DAPTMS修饰芯片的吸附量高于MAPTMS修饰芯片，但吸附层厚度一致，表明DAPTMS表面上BSA存在聚集现象；AFM扫描结果与DPI分析结果一致，证明了配基密度和种类不仅影响界面上蛋白质吸附量，而且影响蛋白质吸附密度和表面聚集行为。

英文摘要：

The effect of interfacial ligands on the adsorption behavior of BSA was investigated using dual polarization interferometry （DPI）. The sensor chips of DPI were modified with 3-aminopropyltriethoxysilane （ APTES ）, （ 3-methylaminopropyl ） trimethoxysilane （ MAPTMS ） and （ 3-diethylaminopropyl ） trimethoxysilane （DAPTMS） respectively. The ligand densities on the modified chips were compared using X-ray photoelectron spectroscopy. The adsorption behaviors of BSA on the three modified chips were characterized using DPI and atomic force microscopy （AFM） respectively. It was found that the adsorbed BSA on the APTES-modified chip occupies a larger area than other ligand-modified ones, suggesting that the higher ligand density led to the more points in binding sites. The ligand density on MAPTMS-modified chip was similar as that on the DAPTMS- modified chip. BSA showed higher BSA adsorption on the DAPTMS-modified chip than the MAPTMS-modified, but the thickness of BSA layers were almost the same, indicating a higher density of BSA adsorbed. AFM images of the BSA adsorbed on the three ligand-modified chips corresponded to the result from DPI detection. The results indicates that the ligand density on the modified chip affects the amount, density and aggregation of BSA on the interfaces.