Characterization of porous β-tricalcium phosphate films formed on alumina ceramics by spray-pyrolysis technique and their in vitro evaluations using osteoblasts

Porous calcium-phosphate films were formed on alumina ceramics by a spray-pyrolysis technique, using two kinds of starting solutions having Ca/P ratios of 0.50 and 1.67. A beta-tricalcium phosphate (beta-TCP) phase was present in the resulting films with a thickness of about 50 mu m. The films were porous and the median pore size was about 105 mu m. After Scotch((R)) tape (#810) adhering to the films was removed from the substrates, the films were still present on the substrate. The biocompatibility of the alumina ceramics coated with beta-TCP (simply referred to as coated specimen) was examined using MC3T3-E1 cells as an osteoblast model. The cells on the coated specimen well proliferated in a similar manner to those cultured polystyrene dish and on uncoated alumina ceramics. The alkaline phosphatase activity of the cells cultured on the coated specimen for 17 d was significantly higher than that of the uncoated alumina ceramics. The present porous beta-TCP films have good cellular responses with respect to cell proliferation and differentiation.