Chemiluminescence-based detection and comparison of protein amounts adsorbed on differently modified silica surfaces

Abstract

The biol. consequences of protein adsorption on biomaterial surfaces are considered to be of utmost importance for their biocompatibility. A new method based on amino group-labeling coupled to a chemiluminescence reaction for direct detn. of proteins adsorbed on material surfaces was employed. This method was used to explore the effects of surface chem. and surface roughness on protein adsorption in a silicon oxide model system. Corundum sandblasting was applied to silicon wafers to create roughened surfaces while immobilization of fluorocarbon-, hydrocarbon-, and poly(ethylene glycol)-contg. silanes produced surfaces of varying wettability. The adsorption behavior of two complex body fluids, human serum and saliva, and of two purified components, human serum albumin and fibronectin, was strongly influenced by the surface parameters. A general tendency to higher amts. of adsorbed protein was found on roughened surfaces and modification with poly(ethylene glycol) or with fluorocarbon moieties reduced protein adsorption. The values obtained with the new method could be confirmed by a colorimetric detn. of protein amts. adsorbed on identically modified silica beads and were in accordance with those previously reported utilizing established methods for protein quantification. The presented method, which was methodically simple to perform and allowed the simultaneous measurement of a large no. of samples, may be of future value for high-throughput surveying of the protein adsorption characteristics of biomaterials.