Mesoporous Silica Coating on Rf-Sputtered Apatite/Titanium Substrate

Abstract

The preparation of mesoporous silica coated rf-sputterd apatite / titanium substrate and protein adsorptive property is reported. Hydroxyapatite coated titanium implant has been used, and the adsorption of proteins onto implant is very important for bond formation between bone and implant. Mesoporous silica (MPS) materials have been extensively studied as carriers of bio-molecules due to their potential practical applications in medical materials. Pore diameters of 1.5 – 30 nm of the periodic mesoporous materials are close to the diameters of target molecules and high adsorbed amount of proteins onto MPS has been reported, and also enclosure of the protein in a well-defined space may help to prevent denaturation. Previously, we reported the MPS coating on the porous hydroxyapatite (HAp) ceramics obtained by dip-coating method, and by the vapor phase synthesis. Protein adsorption on the porous HAp with the MPS coatings was evaluated using UV-VIS spectrometry, and the quantity of adsorbed amount of protein was remarkably improved. In this study, the HAp deposition on Ti substrate (HAp/Ti) was carried out by rf magnetron sputtering and hydrothermal treatment, and MPS coating on HAp/Ti using LB deposition apparatus to improve the protein adsorptive property of HAp/Ti. The quantity of adsorbed protein onto the HAp /Ti was around 12 times high, and that onto the MPS/HAp/Ti was 18 times high compared to that on Ti substrate.