波长检测型表面等离子体子共振生物传感器测定β-环糊精与血清白蛋白的相互作用

Use of Wavelength Modulation Surface Plasmon Resonance Biosensor to Study Interaction of β-CD with Serum Albumin

采用自行组装的表面等离子体子共振(SPR)传感装置,固定入射角,以波长为变量,以电荷耦合器件(CCD)为检测系统,用对金和蛋白质均有较强作用的巯基丙酸作为基底膜,分别监测了β-环糊精(CD)与人血清白蛋白(HSA)、牛血清白蛋白(BSA)反应的动力学过程,并分别计算了它们的动力学常数、热力学常数及键合百分率.此外,对传感器的再生性也进行了研究.结果表明,β-CD与HSA,BSA相互作用的平衡常数分别是7.79和51.00μmol/L,且键合百分率都很高,分别是98.77%和94.25%.这些结果有力地说明了β-CD作为药物载体,可以提高生物利用度,延长药物半衰期.

The wavelength modulation surface plasmon resonance （SPR） biosensor was designed based on fixing the incident angle of light and measuring the reβected intensities at the resonance wavelength simultaneously. The interaction between β-CD and serum albumin （human serum albumin, bovine serum albumin） was studied with the wavelength modulation SPR sensor, and kinetic constants, thermodynamic constants, and binding percentages were obtained, respectively. In addition, regeneration of the SPR biosensor was also studied. This method provides detailed information on affinities of the β-CD binding to serum albumin. The equilibrium constant of the reaction for the β-CD and HSA was 7.79 μmol/L, while that for the β-CD and BSA was 51.00 μmol/L. The binding percentages were 98.77% and 94.25% for β-CD binding HSA and BSA, respectively. These results indicated that their affinities were very high for β-CD towards HSA and BSA.