载米诺环素纳米羟基磷灰石/壳聚糖复合体的体外释放及抑菌性

In vitro release and antibacterial property of minocycline-hydroxyapatite/chitosan complex

背景:研究发现羟基磷灰石/壳聚糖复合体可作为药物载体起到缓释药物的作用,但目前缺乏将米诺环素载入该复合体后对其释放量及抑菌效果的研究。目的:观察载米诺环素的纳米羟基磷灰石/壳聚糖复合体的体外药物释放及抑菌性。方法:采用共沉淀法制备羟基磷灰石/壳聚糖复合体及载米诺环素的纳米羟基磷灰石/壳聚糖复合物。扫描电镜观察材料表面及断面特征;阿基米德原理测量材料孔隙率;以模拟唾液作为释药介质、高效液相色谱法测定盐酸米诺环素释放量;抑菌环法测量材料对牙龈卟啉单孢菌和金黄色葡萄球菌的体外抑菌作用,并通过CCK8细胞增殖实验评价载药材料的生物学毒性。结果与结论:载米诺环素后,载米诺环素的纳米羟基磷灰石/壳聚糖复合物孔隙增大,平均孔隙率为53.99%;单日释放量可长期维持在0.5-1.0μg/d,7 d后仍对牙龈卟啉单孢菌和金黄色葡萄球菌有明显的抑菌环;细胞增殖实验显示载米诺环素的纳米羟基磷灰石/壳聚糖复合物浸提液具有明显促进细胞增殖的作用。提示载米诺环素的纳米羟基磷灰石/壳聚糖复合物纳米复合物能够较长时间地持续缓释米诺环素,对于牙龈卟啉单孢菌和金黄色葡萄球菌均具有良好的抑制作用,并可促进牙周膜细胞的增殖。

BACKGROUND： Hydroxyapatite/chitosan（HA/CS） complex may act as a drug carrier for drug release, but little is reported about the release amount and antibacterial effect of minocycline-HA/CS（Mino-HA/CS） complex. OBJECTIVE： To investigate the in vitro release and antibacterial property of Mino-HA/CS complex. METHODS： HA/CS and Mino-HA/CS were prepared using co-precipitation method. The surface and cross-section features of the complexes were observed under scanning electron microscopy. The porosities were measured according to Archimedes Principle. The release of minocycline hydrochloride was measured by high performance liquid chromatography with the simulated saliva as drug release media. In vitro antibacterial effect on Porphyromonas gingivalis and Staphylococcus aureus were measured by bacteria-inhibiting ring method. Biological toxicities were evaluated via cell counting kit-8cell proliferation assay. RESULTS AND CONCLUSION： The porosity of Mino-HA/CS was larger than that of HA/CS, with the average porosity of 53.99%. Single-day release amount of Mino-HA/CS could maintain at the level of 0.5-1 μg per day for a long-term. Bacteriostatic rings of Porphyromonas gingivalis and Staphylococcus aureus still existed clearly after 7 days. Cell proliferation assays showed that Mino-HA/CS extract had the significant effect on promoting cell proliferation. These findings indicate that the Mino-HA/CS sustains the release of minocycline at a relatively stable level within a longer period, shows good inhibitory effect on Porphyromonas gingivalis and Staphylococcus aureus and promotes the proliferation of periodontal ligament cells.