Kinetic studies of bone demineralization at different HCl concentrations and temperatures

The goal of this study was to contribute to the interpretation of the kinetics involved in the in vitro demineralization process of bone, which has clinical uses as bone grafts (demineralized bone matrix), as well as for materials science applications. Cortical and cancellous bovine femur bones and cortical antler were demineralized in dilute hydrochloric acid and the kinetic parameters of the demineralization reaction at different temperatures and HCl concentrations were calculated. The rate of demineralization increased with both HCl concentration and temperature. During the demineralization reaction experiments, three different stages were clearly identified: a) in the first stage, the rate constant increased as HCl advanced from the periphery to the core of the sample. b) In the second stage, the demineralization occurred at a steady state, and finally, c) in the third stage, the rate constant diminished. The activation energy for demineralization was calculated for both types of bones.