ELECTROPHORETIC GELS OF DENTIN MATRIX PROTEINS AS DIFFUSION MEDIA FORIN-VITRO MINERALIZATION

Non-collagenous proteins of dentin and bone have important-effects on mineralization which have been studied by various in vitro systems. We developed an in vitro mineralization system using electrophoretic gel s as diffusion media of calcium and phosphate ions. Calcium and phosph ate ions were diffused naturally or propelled by electric potential. C alcium phosphate was precipitated in the gel, and the precipitation wa s affected by proteins in the gel which had been separated by electrop horesis. We applied this system to analysis of non-collagenous protein s of dentin. Among the proteins, phosphophoryns promoted calcium phosp hate precipitation in the natural-diffusion system. A non-collagenous protein having a molecular mass of 60 kDa inhibited precipitation. The results were different, however, in the electric-diffusion system, in which phosphophoryns had a negative effect. The present system enable d us to compare the effects of plural proteins rapidly, even using unp urified material.