期刊
SOFT MATTER
卷 8, 期 5, 页码 1428-1436出版社
ROYAL SOC CHEMISTRY
DOI: 10.1039/c1sm06894f
关键词
-
类别
资金
- Deutsche Forschungsgemeinschaft, Schwerpunkt Hydrogele
We present a thermodynamic study of the adsorption of lysozyme on a negatively charged core-shell microgel at pH 7.2. The carrier particles consist of a polystyrene core onto which a charged poly (N-isopropylacrylamide-co-acrylic acid) network is attached. Isothermal titration calorimetry (ITC) is used to investigate the temperature and salt dependence of lysozyme binding. Our ITC analysis unequivocally shows that the adsorption of lysozyme onto the charged gel is driven by entropy. The addition of salt strongly decreases the binding affinity, indicating significant electrostatic contributions to the adsorption process. However, at high salt concentrations, substantial protein binding with unaltered entropies is still observed pointing to large contributions from hydrophobic interactions. Furthermore, the calorimetric analysis suggests that protonation of lysozyme takes place upon binding. This is directly shown by analysis of the enzymatic activity of adsorbed lysozyme. It was found that the activity is enhanced about similar to 3.5 times, indicating that lysozyme has taken up approximately one proton when entering the gel. The entire set of data demonstrates that core-shell microgels present smart'' colloidal carriers for lysozyme that enhance its activity.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据