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目的:评价碱性磷酸酶(alkaline phosphatase,AP)控释的仿生矿化体系中磷灰石结合肽对钙磷成核及早期晶体生长的影响.方法:固相合成环肽(NH2-CLPLWYPSC-COOH,CLP).构建AP控释的仿生矿化系统.监测磷酸根离子的释放速率及OD820 nm的变化并于扫描电子显微镜(SEM)下观察产物形貌.比较牛血清白蛋白(bovine serum albumin,BSA)和CLP添加剂对钙磷成核及早期晶体生长的影响.结果:磷酸根离子在矿化起始的0～30 min内持续释放;所观测时间范围内,BSA促进矿化发生且OD820 nm明显高于空白组和CLP组(P<0.05),而CLP抑制矿化反应的发生.SEM结果提示,CLP与矿化前驱体发生相互作用并改变其形貌.结论:AP控释的溶液矿化体系有利于监测CLP对晶体成核及生长的影响,BSA是矿化促进剂而CLP作用于矿化前体,抑制早期的晶体形成并影响其生长方式.“,”Objective:To evaluate the regulating effects of an apatite binding peptide on nucleation and growth of calcium phosphate nanoparticles in an in vitro biomimetic mineralization system,in which the release rate of phosphate ion is controlled by alkaline phosphatase( AP) . Methods:The cyclic peptide( NH2-CLPLWYPSC-COOH,CLP) was synthesized u-sing a solid phase method. The release rate of phosphate ion and the changes of OD820 nm were monitored in an AP-mediated biomimetic mineralization system. The morphology of the precipitates was observed under a scanning electron microscope ( SEM) . Results:Phosphate ions were continuously released within the first 30 min. The highest rate of increase in optical ab-sorbance was observed in the bovine serum albumin( BSA) group. In the presence of CLP,the increase of the absorbance was reduced and the morphology the mineralized precursors revealed a layer structure. Conclusion:The AP-mediated biomimetic mineralization system is suitable for monitoring the regulating effects of additives in initial stage of calcium phosphate precipi-tation. BSA accelerate the reaction while CLP act as an inhibitor which interacts with mineralized precursors and changes the crystal growth patterns.