Wassell D T, Embery G
Department of Basic Dental Science, Cardiff Dental School, University of Wales College of Medicine, Cardiff, UK.
Biomaterials. 1996 May;17(9):859-64. doi: 10.1016/0142-9612(96)83280-7.
The adsorption of bovine serum albumin (BSA) on to titanium powder has been studied as a function of protein concentration and pH, and in the presence of calcium and phosphate ions. Isotherm data have shown that the adsorption process does not follow the Langmuir model (inflection points). The maximum adsorption (Admax) at pH 6.8 is 1.13 +/- 0.21 mg m-2. For the pH dependence of adsorption the amount adsorbed increases with decreasing pH (at pH 5.15 Admax = 1.31 +/- 0.2 mg m-2), indicating that hydration effects are important. Adsorption increases and decreases in the presence of calcium (at pH 6.8 for 0.002 M Admax = 1.73 +/- 0.23 mg m-2) and phosphate (at pH 6.8 for 0.002 M Admax = 0.64 +/- 0.14 mgm-2)ions, respectively, indicating that electrostatic effects are important. The time dependence, isotherm and desorption data provide indirect evidence of possible conformational changes in the BSA molecule.
研究了牛血清白蛋白（BSA）在钛粉上的吸附情况，该吸附是蛋白质浓度、pH值以及钙和磷酸根离子存在与否的函数。等温线数据表明，吸附过程不符合朗缪尔模型（存在拐点）。在pH 6.8时的最大吸附量（Admax）为1.13±0.21 mg m-2。对于吸附的pH依赖性，吸附量随pH降低而增加（在pH 5.15时，Admax = 1.31±0.2 mg m-2），这表明水合作用很重要。在钙（在pH 6.8时，0.002 M时Admax = 1.73±0.23 mg m-2）和磷酸根（在pH 6.8时，0.002 M时Admax = 0.64±0.14 mg m-2）离子存在时，吸附分别增加和减少，这表明静电作用很重要。时间依赖性、等温线和解吸数据为BSA分子可能的构象变化提供了间接证据。
