Adsorption and displacement of a globular protein on hydrophilic and hydrophobic surfaces
Adsorption and displacement of a globular protein on hydrophilic and hydrophobic surfaces
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DOI：
10.1016/s0927-7765(01)00204-1
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发表时间：
2002-01-01
影响因子：
5.8
通讯作者：
Sferrazza, M
中科院分区：
文献类型：
--
作者：
Marsh, RJ;Jones, RAL;Sferrazza, M
研究了球形蛋白β-乳球蛋白在亲水和疏水表面的吸附行为。利用椭圆偏振光谱和傅里叶变换红外光谱技术，在衰减全反射模式下进行了实验研究。β-乳球蛋白的表面吸附浓度小于或等于紧密堆积的单分子层所对应的表面浓度。用缓冲溶液洗脱后，从亲水性表面上去除的g-乳球蛋白的量，作为吸附最终量的一部分，随着吸附时间的延长而减少。这提供了证据，证明吸附的蛋白质一旦被吸附，构象变化相对较慢，导致更不可逆的吸附状态，与表面具有更强的结合。蛋白质不可逆吸附在疏水表面的比例普遍高于亲水表面，证实了球状蛋白与疏水表面的结合比亲水表面更强的一般规律。还研究了非离子表面活性剂十八醇十二烷基醚(C12E8)对蛋白质疏水和亲水表面预吸附层的置换作用。我们观察到，非离子表面活性剂导致吸附的蛋白质从疏水表面部分置换。置换动力学还表明，蛋白质层在较长的时间内比在较短的吸附时间内更强地结合在疏水表面上，这表明蛋白质结合的缓慢变化和老化效应在疏水表面也是重要的。(C)2002 Elsevier Science B.V.保留所有权利。
The adsorption of the globular protein beta-lactoglobulin on hydrophilic and hydrophobic surfaces has been investigated. Spectroscopic ellipsometry and Fourier transform infrared spectroscopy in the attenuated total reflection mode were used in our study. beta-lactoglobulin adsorbed in surface concentrations less than or equal to those corresponding to a closely packed monolayer of molecules. The amount of g-lactoglobulin removed from hydrophilic surfaces upon elution with buffer solution, as a fraction of the final amount reached upon adsorption, was observed to decrease at longer adsorption times. This provides evidence that the conformation of the adsorbed protein changes relatively slowly once adsorbed, leading to more irreversibly adsorbed states with stronger binding to the surface. The fraction of protein irreversibly adsorbed to the surface was generally higher on hydrophobic surfaces than hydrophilic surfaces, confirming the general principle that globular proteins exhibit stronger binding to hydrophobic surfaces than hydrophilic ones. The displacement of pre-adsorbed layers of the protein from hydrophobic and hydrophilic surfaces by the non-ionic surfactant octaethylene glycol monododecyl ether (C12E8) was also studied. We observed that the non-ionic surfactant caused partial displacement of adsorbed protein from hydrophobic surfaces. The displacement kinetics also reveal that the protein layers are more strongly bound to hydrophobic surfaces at longer than at shorter adsorption times, showing that slow protein binding changes and ageing effects are also important at hydrophobic surfaces. (C) 2002 Elsevier Science B.V. All rights reserved.