Lyotropic liquid crystals (LLC) have received increasing attention as a drug delivery system. In this study, a novel intra-canal disinfectant based on the glycerol monooleate (GMO) LLC precursor incorporation with chlorhexidine (CHX) and silver nanoparticles (Ag-NPs) was designed and evaluated. The LLC precursor with excellent fluidity was able to penetrate deeply into the complex tiny collateral branch root canals. The transformation of cubic LLC in root canals upon coming into contact with water provided long-lasting disinfection against multidrug-resistant bacteria to avoid the endodontic reinfection and follow-up visits. The GMO–ethanol–water (48% : 12% : 40%, w/w) formulation containing 0.5% CHX and 0.02% Ag-NPs was selected for further studies. The low viscosity of the precursor presented excellent injectability and flowabilities. From the in vitro release test, the release behaviours were found to be influenced by CHX and Ag-NP contents, allowing the optimized precursor to obtain a 28-day release profile. The CHX-Ag-NP containing LLC precursor exhibited an excellent and sustained sterilization effect on Enterococcus faecalis for more than one month with a bacterial inactivation rate of ≥98.5%, which was far more than the minimum clinical requirement (7 days). Furthermore, no in vitro toxicity was observed in the cytotoxicity evaluation. The CHX-Ag-NP containing LLC precursor was proved to be a promising intra-canal disinfectant in our study.

中文翻译：

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掺入醋酸洗必泰和银纳米颗粒的液晶前体，用于根管消毒

溶致液晶（LLC）作为药物递送系统已受到越来越多的关注。在这项研究中，设计并评估了一种基于甘油单油酸酯（GMO）LLC前驱体与洗必泰（CHX）和银纳米颗粒（Ag-NPs）结合的新型腔内消毒剂。具有出色流动性的LLC前体能够深深地渗透到复杂的细小侧支根管中。与水接触后，根管中的立方LLC转化提供了对耐多药细菌的持久消毒，从而避免了牙髓再次感染和随访。选择含有0.5％CHX和0.02％Ag-NPs的GMO-乙醇-水（48％：12％：40％，w / w）配方进行进一步研究。前体的低粘度具有出色的可注射性和流动性。来自在体外释放测试中，发现释放行为受CHX和Ag-NP含量的影响，从而使优化的前体获得28天的释放曲​​线。含CHX-Ag-NP的LLC前体对粪肠球菌表现出优异且持续的杀菌效果超过一个月，细菌灭活率≥98.5％，远远超过了最低临床要求（7天）。此外，在细胞毒性评价中未观察到体外毒性。在我们的研究中，含CHX-Ag-NP的LLC前体被证明是一种很有前途的运河内消毒剂。