Silin V, Weetall H, Vanderah DJ
Biotechnology Division, National Institute of Standards and Technology, Gaithersburg, Maryland, 20899
J Colloid Interface Sci. 1997 Jan 1;185(1):94-103. doi: 10.1006/jcis.1996.4586.
The nonspecific binding of human immunoglobulin G (hIgG) and bovine serum albumin (BSA) was studied on gold surfaces modified by self-assembled alkyl thiol monolayers (SAMs) with the following terminal groups: CH3, C6H4OH, COO-, NH2, OH, and oligoethylene oxide (OEO). The kinetics of hIgG and BSA adsorption and desorption were monitored in real time utilizing the surface plasmon resonance (SPR) technique with a flow cell. The surface concentration of hIgG molecules adsorbed on the SAMs decreased in the order: CH3 > C6H5OH > COO- > NH2 > OH > OEO SAM surfaces. Binding of BSA to the SAM surfaces decreased in the order: C6H5OH > CH3 > COO- > NH2 > OH > OEO. The results show that on the OEO SAM, the surface concentration of these proteins was less than 0.5 ng/cm2 (the detection limit of our SPR device) and approximately 10(3) times less than that on the hydrophobic CH3-terminated SAM surfaces. The kinetics of the binding curves for the adsorption of the proteins are described in terms of multiple states of adsorbed proteins that involve multipoint hydrophobic, electrostatic, and hydrogen bond interactions for the different surfaces and protein lateral interactions caused by the unfolding of adsorbed proteins.
研究了人免疫球蛋白G（hIgG）和牛血清白蛋白（BSA）在由具有以下端基的自组装烷基硫醇单分子层（SAMs）修饰的金表面上的非特异性结合：CH3、C6H4OH、COO-、NH2、OH和低聚环氧乙烷（OEO）。利用带有流通池的表面等离子体共振（SPR）技术实时监测hIgG和BSA的吸附和解吸动力学。吸附在SAMs上的hIgG分子的表面浓度按以下顺序降低：CH3＞C6H5OH＞COO-＞NH2＞OH＞OEO SAM表面。BSA与SAM表面的结合按以下顺序降低：C6H5OH＞CH3＞COO-＞NH2＞OH＞OEO。结果表明，在OEO SAM上，这些蛋白质的表面浓度小于0.5 ng/cm2（我们的SPR设备的检测限），比疏水性CH3端基SAM表面上的浓度低约103倍。蛋白质吸附的结合曲线动力学是根据吸附蛋白质的多种状态来描述的，这些状态涉及不同表面的多点疏水、静电和氢键相互作用以及由吸附蛋白质展开引起的蛋白质横向相互作用。
