Effect of pH on the adsorption and interactions of Bovine Serum Albumin with functionalized silicon nitride surface.

Force-distance curves between atomic force microscopy (AFM) tip (SN non-functionalized) and bovine serum Albumin (BSA) immobilized on SN substrates have been performed with the purpose to understand how multiple interactions between the protein and the tip were favored in different pHs (4, 6 and 10). In this work, 100 silicon wafer samples were used to deposit a layer of SiN. Protein immobilization consisted of the silanization of the substrates with 3-aminopropyltriethoxysilane (APTES) and crosslinking with glutaraldehyde (GA).