OBJECTIVE Ciprofloxacin (CIP) was effective in treating bacterial keratitis. The purpose of this study was to prepare an effective prolonged-release of CIP by both temperature and pH-triggered in situ nanogels for the treatment of keratitis. MATERIALS AND METHODS Poly(N-isopropylacrylamide-methacrylicacide-vinylpyrrolidone) [P (NIPAAm-MAA-VP)] nanoparticles was synthesised and used for preparation of CIP-loaded nanogels. Antimicrobial and in vivo animal studies of the CIP-loaded nanoformulation were performed. RESULTS Nanoformulation with a mean particle size between 10 and 50 nm and higher than 95% encapsulation efficiency was obtained. Ciprofloxacin released from the nanoparticles showed an enhanced antibacterial effect as determined by minimal inhibitory concentrations. In vivo studies demonstrated reasonable efficacy in severe keratitis using the developed nanoformulation. CONCLUSIONS Nanoformulation had acceptable efficacy in treating bacterial keratitis in an animal model. Therefore, the developed system has the potential to be used in localised application for the treatment of keratitis.

中文翻译：

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原位凝胶系统的制备和体内评估，作为持续热眼药物输送的双重热/ pH响应纳米载体。

目的环丙沙星（CIP）可有效治疗细菌性角膜炎。这项研究的目的是通过温度和pH触发的原位纳米凝胶制备CIP的有效延长释放，以治疗角膜炎。材料与方法合成了聚（N-异丙基丙烯酰胺-甲基丙烯酰胺-乙烯基吡咯烷酮）[P（NIPAAm-MAA-VP）]纳米颗粒，用于制备CIP负载的纳米凝胶。进行了CIP载纳米制剂的抗菌和体内动物研究。结果获得了平均粒径在10至50 nm之间且包封效率高于95％的纳米制剂。从纳米颗粒释放的环丙沙星显示出增强的抗菌作用，这是通过最小抑菌浓度确定的。体内研究表明，使用开发的纳米制剂，在严重的角膜炎中具有合理的疗效。结论纳米制剂在治疗动物模型性细菌性角膜炎方面具有可接受的疗效。因此，开发的系统有潜力在局部应用中用于治疗角膜炎。