Biological Effects of Nanohydroxyapatite Materials and Its Toxicity

Biological effects of the nanohydroxyapatites materials and its toxicity have been studied using ultraviolet absorption spectrum, infrared spectrum of absorption and MTT method. The nanohydroxyapatites are prepared and made by using Sol-gel method, in which the parameters of process and reaction are controlled as: PH> 9, Ca / P = 1.67, sintering temperature of 1100°C and sintering time 2 hours. Studied results show that nanohydroxyapatites can adsorb the amino acid molecules, the more stronger of acidity of amino acids, the more larger of ability of the absorption. Meanwhile we find that the nanohydroxyapatites and complex of nanoHAP+ nanoCrO₂ can all restrain the proliferation of cells, but their toxicitis are all first degree or ninor, but the restrained effect of the latter is smaller than that of the former, although they can decrease the relative proliferation rate of cells. This is a new and interesting result.