Mochizuki Chihiro, Sasaki Yuji, Hara Hiroki, Sato Mitsunobu, Hayakawa Tohru, Yang Fei, Hu Xixue, Shen Hong, Wang Shenguo
Faculty of Engineering, Kogakuin University, Tokyo, Japan.
J Biomed Mater Res B Appl Biomater. 2009 Jul;90(1):290-301. doi: 10.1002/jbm.b.31285.
Apatite compounds with different levels of crystallinity were prepared using Ca-EDTA complexes. Ca-deficient hydroxyapatite (CDHA) with low crystallinity was synthesized by ultrasonic stirring of a mixture of Ca-EDTA complex, phosphoric acid, and ammonium hydroxide in hydrogen peroxide aqueous solution. Mixtures of carbonate hydroxyapatite (HA) and CDHA with higher crystallinity were also prepared from a solution involving the same complex. The porous composites with lower or higher crystallinity apatite with a copolymer of poly(L-lactide-co-glycilide)(70/30) (PLGA(70/30)) were fabricated by a solution-casting/particles leaching method. The apatites and porous composites were characterized, and it was found that the degradation of composites of apatite with a low level of crystallinity was fastest in phosphate-bufferd saline (PBS) solution compared with other apatite composites with higher levels of crystallinity; however, the rate was smaller than that of PLGA alone. Plasma treatment influenced the degradation of composites in PBS and apatite precipitation in simulated body fluid (SBF). Hydroxyapatite deposition on the PLGA composite with the low crystallinity occurred six times faster than that on PLGA alone after immersion in SBF. The incorporation of apatite into the PLGA matrix did not cause any adverse effects on cell attachment in an assay employing human gingival fibroblasts. This study suggested that the current apatite and PLGA porous composite will be a promising scaffold material for tissue engineering.
使用钙 - 乙二胺四乙酸（Ca-EDTA）络合物制备了具有不同结晶度水平的磷灰石化合物。通过在过氧化氢水溶液中超声搅拌Ca-EDTA络合物、磷酸和氢氧化铵的混合物，合成了低结晶度的缺钙羟基磷灰石（CDHA）。还从包含相同络合物的溶液中制备了具有较高结晶度的碳酸羟基磷灰石（HA）和CDHA的混合物。通过溶液浇铸/颗粒沥滤法制备了具有低结晶度或高结晶度磷灰石与聚（L-丙交酯-共-乙交酯）（70/30）（PLGA(70/30)）共聚物的多孔复合材料。对磷灰石和多孔复合材料进行了表征，发现与其他具有较高结晶度的磷灰石复合材料相比，低结晶度磷灰石复合材料在磷酸盐缓冲盐水（PBS）溶液中的降解速度最快；然而，该速度比单独的PLGA小。等离子体处理影响了复合材料在PBS中的降解以及在模拟体液（SBF）中的磷灰石沉淀。在SBF中浸泡后，低结晶度的PLGA复合材料上羟基磷灰石的沉积速度比单独的PLGA快六倍。在使用人牙龈成纤维细胞的测定中，将磷灰石掺入PLGA基质对细胞附着没有造成任何不利影响。这项研究表明，当前的磷灰石和PLGA多孔复合材料将是一种有前途的组织工程支架材料。
