Mateos Helena, Valentini Alessandra, Lopez Francesco, Palazzo Gerardo
CSGI (Center for Colloid and Surface Science), via Orabona 4, 70125 Bari, Italy.
School of Chemical Engineering, University of Birmingham, Birmingham B15 2TT, UK.
Biomimetics (Basel). 2020 Jul 1;5(3):31. doi: 10.3390/biomimetics5030031.
Surface interactions with polymers or proteins are extensively studied in a range of industrial and biomedical applications to control surface modification, cleaning, or biofilm formation. In this study we compare surfactant interactions with protein-coated silica surfaces differing in the degree of curvature (macroscopically flat and colloidal nanometric spheres). The interaction with a flat surface was probed by means of surface plasmon resonance (SPR) while dynamic light scattering (DLS) was used to study the interaction with colloidal SiO (radius 15 nm). First, the adsorption of bovine serum albumin (BSA) with both SiO surfaces to create a monolayer of coating protein was studied. Subsequently, the interaction of these BSA-coated surfaces with a non-ionic surfactant (a decanol ethoxylated with an average number of eight ethoxy groups) was investigated. A fair comparison between the results obtained by these two techniques on different geometries required the correction of SPR data for bound water and DLS results for particle curvature. Thus, the treated data have excellent quantitative agreement independently of the geometry of the surface suggesting the formation of multilayers of CPEG over the protein coating. The results also show a marked different affinity of the surfactant towards BSA when the protein is deposited on a flat surface or individually dissolved in solution.
在一系列工业和生物医学应用中，人们广泛研究了聚合物或蛋白质与表面的相互作用，以控制表面改性、清洁或生物膜形成。在本研究中，我们比较了表面活性剂与曲率不同的蛋白质包覆二氧化硅表面（宏观平坦表面和胶体纳米球）的相互作用。通过表面等离子体共振（SPR）探测与平坦表面的相互作用，而动态光散射（DLS）用于研究与胶体SiO（半径15nm）的相互作用。首先，研究了牛血清白蛋白（BSA）在两种SiO表面上的吸附，以形成单层包覆蛋白质。随后，研究了这些BSA包覆表面与非离子表面活性剂（平均含有八个乙氧基的乙氧基化癸醇）的相互作用。要对这两种技术在不同几何形状上获得的结果进行合理比较，需要对SPR数据进行结合水校正，对DLS结果进行颗粒曲率校正。因此，处理后的数据具有极好的定量一致性，与表面几何形状无关，表明在蛋白质涂层上形成了CPEG多层膜。结果还表明，当蛋白质沉积在平坦表面上或单独溶解在溶液中时，表面活性剂对BSA的亲和力存在显著差异。
