Protein Adsorption on Solid Surfaces

It has been found that biological implants are often rejected by the host body. It is caused by excessive adsorption of proteins onto the surface of the implant. It is believed that decreasing protein adsorption would hopefully prolong the lifespan of the implant. The adsorption of protein from aqueous solution onto solid surfaces is studied using the Quartz Crystal Microbalance (QCM). It detects only the mass of the protein that is adsorbed onto the solid surface of the QCM crystal in an aqueous medium. Bovine serum albumin (BSA) and tau proteins are studied on gold surfaces, and interactions with mica surfaces using QCM is still in progress. Preliminary studies with Atomic Force Microcopy (AFM) images of BSA on mica surfaces show a major difference in the pH level of the solution and also in different salt concentration. However, there is little dependence on the concentration of BSA. Studies from AFM images of tau protein interactions with mica are currently in progress. Combining the preliminary studies with the QCM technique, we hope to find the approximate amount of BSA or tau protein adsorbed onto the solid surface of gold or mica covered QCM crystals.