甲硝唑缓释牙胶尖的制备及体外释放实验

目的:研制一种用于根管消毒的甲硝唑缓释系统,测定其体外持续释放有效药物浓度的时间。方法:选择牙胶尖为载体,吸附甲硝唑等制备成药尖,聚乙二醇-1500与醋酸纤维素分别按不同比例混合作缓释膜,制成4组甲硝唑缓释牙胶尖(SRDGM),根据4组缓释剂的体外释放度及相应参数,选择释放甲硝唑有效药物浓度时间最长的一组作为实验用的缓释剂。选8颗单根管离体牙,SRDGM作根管消毒剂,紫外分光光度法测定体外释放度。结果:SRDGM含甲硝唑2013μg,24h释出全部药量的68.24%。SRDGM在离体牙根管内持续释放有效药物浓度达10d以上,第10天释出药物浓度33.13μg/ml,超过甲硝唑的最低抑菌浓度。结论:本研究研制的SRDGM可以载送药物,并控制释放;能在根管内维持一定时间的有效药物浓度达10d以上,防止根管再感染。

The preparation and in vitro release test of sustained release delivery gutta-percha point containing metronidazole

PURPOSE: To develop sustained release delivery gutta-percha point containing metronidazole (SRDGM) for root canal disinfection, and determine the drug concentration in vitro and the time that the device maintains the effective drug concentration. METHODS: The gutta-percha was selected as the carrier and adsorbed metronidazole etc. The point was coated with mixation of ployethylene glycol and acetate fibre to prepare the groups of SRDGM.The group that released the longest period of the effective drug was selected for the following study. Eight teeth were selected, the SRDGM was used to disinfect the root canal. The adsorption was measured for 24 hours and 10 days. RESULTS: The SRDGM contained metronidazole 2013 microg, it could release 68.24% of the total drug in 24 hours in vitro. The effective metronidazole concentration released lasted more than 10 days. On the 10th day, there was also 33.13 microg/ml metronidazole released which was more than minitory inhibitory concentration of metronidazole. CONCLUSIONS: SRDGM could carry the metronidazole and control the release rate. It could maintain the effective drug concentration for a long time (>10 days) in root canal.