Adsorption of BSA on Highly Carboxylated Microspheres—Quantitative Effects of Surface Functional Groups and Interaction Forces

摘要: In order to elucidate the relations between amount of surface functional groups and interaction forces, BSA adsorption experiments were performed, using highly carboxylated PS/PMAA microspheres as well conventional ones. Two kinds forces considered in this study, hydrogen bonding hydrophobic interactions, while ionic interactions assumed be small or constant. Hydrophobic dominant lowNc(number density carboxyl groups) region, below 1 group nm−2, relatively sensitive pH, was highNcregion, above 2 irrespective pH. The transition region these two ∼ nm−2on a microsphere. When comparing extremes bonding, latter stronger, which different from earlier studies. It can explained that do not have enough on their surfaces. Adsorption constantKdiminished asNcincreased, means affinity itself is reduced by bonding. Adsorbed layer thicknesses calculated theCm(adsorbed equilibrium) 4.66 7.08 nm; molecules exist side-on end-on mode.