Synthesis of a novel beta-tricalcium phosphate/hydroxyapatite biphasic calcium phosphate containing niobium ions and evaluation of its osteogenic properties.
To promote the osteogenic properties of osteoblasts, we synthesized a hydroxyapatite (HAp) with beta-tricalcium phosphate (beta-TCP) biphasic calcium phosphate containing Nb ions (NbTCP/HAp). NbTCP/HAp was prepared by annealing precipitates obtained by coprecipitation of an aqueous solution of Ca(NO(3))(2) and a mixture of (NH(4))(2)HPO(4) and aqueous Nb solution. The precipitates can be regarded as a calcium-deficient HAp, the PO(4) sites of which are partly occupied by Nb ions. NbTCP/HAp was successfully synthesized by thermal decomposition of the precipitates. NbTCP/HAp enhanced the calcification of normal human osteoblasts (NHOst), and the amount of calcified tissue increased in proportion to the Nb ion concentration in the NbTCP/HAp. The alkaline phosphatase (ALP) activity of NHOst was also enhanced by NbTCP/HAp. Because Nb ions significantly enhance the ALP activity of NHOst, calcification by NbTCP/HAp is considered to be due to enhancement of ALP activity induced by Nb ions dissolved from NbTCP/HAp. These results indicate that NbTCP/HAp can be an effective bone repair material.
Tamai
Masato
M
Division of Medical Devices, National Institute of Health Sciences, 1-18-1 Kamiyoga, Tokyo, Japan.
Isama
Kazuo
K
Nakaoka
Ryusuke
R
Tsuchiya
Toshie
T
D002130:Calcium Phosphates / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D006882:Hydroxyapatites / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D009556:Niobium / Q000494:pharmacology*; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D010006:Osteoblasts / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects*; D023822:Tissue Engineering
D002130:Calcium Phosphates; D006882:Hydroxyapatites; D009942:Organometallic Compounds; C485817:beta-tricalcium phosphate; D009556:Niobium