Glasses incorporating increasing amounts of bovine serum albumin were prepared by sol-gel techniques from a tetra methoxy silane precursor. The surface of the glass samples was studied by X-ray photoelectron spectroscopy, revealing that the protein is present also in the superficial layer of the silica network. Moreover, the protein is distributed in a dose-dependent way, since the N/Si atomic ratio increases linearly with the albumin concentration in the reaction mixture. Angle-dependent measurements show that the protein distribution occurs homogeneously and is the same at different sampling depths. Protein incorporation in the bulk SiO2 network, with a uniform protein distribution between bulk and surface, is confirmed by infrared spectroscopy measurements, performed both in reflectance and transmittance mode. The reaction with a specific antibody and the adhesivity assay of osteoblastic cells show that embedded albumin present on the glass surface is able to interact with other proteins.
Iucci, G., Infante, G., Rossi, L., Polzonetti, G., Rosato, N., Avigliano, L., et al. (2004). Albumin-containing sol-gel glasses: Chemical and biological study. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE, 15, 601-606 [10.1023/B:JMSM.0000026381.58969.e9].