口腔长效抑菌缓释剂的制备与研究

Preparation and study of oral sustained-release formulation with long-acting bacteriostasis

通过测定多种牙膏常用的抑菌药物的最低抑菌浓度(MIC),发现西吡氯铵(CPC)和氯己定对变异链球菌和牙龈卟啉单胞菌均具有强烈的抑制作用,其MIC均低于1 mg/L。利用三乙酰基-β-环糊精(TA-CD)和乙基纤维素(EC)对CPC进行包裹,喷雾干燥制样,得到的载药颗粒具有明显的"暴释"现象,加入硬脂酸(SA)后,载药颗粒表现出更好的缓释效果。另外,在载药颗粒中添加一定量的聚乙烯醇(PVA),可以明显提升载药颗粒刷牙后在口腔的附着率,当PVA的质量分数为20%时,载药颗粒的附着率最高,达到19.1%。利用混合菌生物膜对DLP-7载药颗粒和CPC进行抑菌评价,实验结果表明,随着时间延长,载药颗粒抑菌率不断增加,4 h后其抑菌率要明显高于CPC对于生物膜的抑菌率,即DLP-7载药颗粒体现出长效的抑菌效果。

By measuring the minimal inhibitory concentration（ MIC） of various antibacterial drugs commonly used in toothpaste,it is found that both cetylpyridinium chloride（ CPC） and chlorhexidine have strong bacteriostatic effect on Streptococcus mutans and Porphyromonas gingivalis with the MIC below 1 mg/L. The CPC was coated with triacetyl-β-cyclodextrin（ TA-CD） and ethyl cellulose（ EC） and particles were prepared by spray drying. The drug-loaded particles had obvious ＂burst release＂phenomenon,and it showed better sustained release effect after adding stearic acid（ SA）. In addition,the adhesion rate of the drug-loaded particles can be significantly improved after brushing,when certain amount of polyvinyl alcohol（ PVA） was added. When the mass fraction of PVA is 20%,the adhesion rate of the drug-loaded particles is the highest,reaching 19. 1%. The mixed bacterium biofilm was used to evaluate the bacteriostasis of drug-loaded particle（ DLP-7） and CPC. The results show that the relative inhibition rate of drug-loaded particles increases continuously over time. After 4 h,the relative inhibition rate of DLP-7 is higher than CPC,which means that DLP-7 shows long-acting bacteriostasis.