School of Chemical Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, 14300 Nibong Tebal, S.P.S., Penang, Malaysia.
Colloids Surf B Biointerfaces. 2013 Oct 1;110:248-53. doi: 10.1016/j.colsurfb.2013.05.001. Epub 2013 May 9.
Protein adsorption onto membrane surfaces is important in fields related to separation science and biomedical research. This study explored the molecular interactions between protein, bovine serum albumin (BSA), and nitrocellulose films (NC) using electrokinetic phenomena and the effects of these interactions on the streaming potential measurements for different membrane pore morphologies and pH conditions. The data were used to calculate the streaming ratios of membranes-to-proteins and to compare these values to the electrostatic or hydrophobic attachment of the protein molecules onto the NC membranes. The results showed that different pH and membrane pore morphologies contributes to different protein adsorption mechanisms. The protein adsorption was significantly reduced under conditions where the membrane and protein have like-charges due to electrostatic repulsion. At the isoelectric point (IEP) of the protein, the repulsion between the BSA and the NC membrane was at the lowest; thus, the BSA could be easily attached onto the membrane/solution interface. In this case, the protein was considered to be in a compact layer without intermolecular protein repulsions.
蛋白质在膜表面的吸附在分离科学和生物医学研究等相关领域中非常重要。本研究利用电动现象研究了蛋白质（牛血清白蛋白，BSA）与硝酸纤维素膜（NC）之间的分子相互作用，以及这些相互作用对不同膜孔径形态和 pH 值条件下流动电势测量的影响。该数据用于计算膜-蛋白质的流动比，并将这些值与蛋白质分子在 NC 膜上的静电或疏水附着进行比较。结果表明，不同的 pH 值和膜孔径形态导致了不同的蛋白质吸附机制。由于静电排斥，在膜和蛋白质带同种电荷的情况下，蛋白质吸附显著减少。在蛋白质的等电点（IEP）时，BSA 和 NC 膜之间的排斥力最低，因此，BSA 很容易附着在膜/溶液界面上。在这种情况下，蛋白质被认为处于没有分子间蛋白质排斥的紧凑层中。
