长效黏膜黏附型微胶囊的构建及在幽门螺杆菌感染小鼠中的应用

目的: 制备一种能长效黏膜滞留且有CT示踪成像功能的微胶囊，用于治疗幽门螺杆菌感染。方法: 首先利用N (3 二甲基氨基丙基) N′ 乙基碳二亚胺盐酸盐（EDC）催化的酰胺反应，制备具有黏膜黏附功能的儿茶酚化壳聚糖。然后通过静电喷雾和聚电解质自组装方法，原位合成具有硫酸钡沉淀的儿茶酚化微胶囊（Cat C/A@BS MCs）。对幽门螺杆菌感染小鼠连续灌胃载阿莫西林微胶囊10 d，评价其体重变化及快速尿素酶试验强度。结果： 成功制备了形态均一、粒径约500 μm的Cat C/A@BS MCs。Cat C/A@BS MCs具有良好的CT成像能力，可在小鼠消化道内滞留长达48 h。小鼠体内实验结果证实，Cat C/A@BS MCs可有效提高阿莫西林对幽门螺杆菌感染的清除率。结论： 成功构建黏膜黏附与CT成像双功能微胶囊，制备的微胶囊能显著提升阿莫西林对幽门螺杆菌感染的清除。

Construction of long-lasting gastric mucoadhesive microcapsules applied to mice infected with Helicobacter pylori

Objective: To prepare a specific microcapsule with long acting mucosal adhesion and CT imaging used for the treatment of Helicobacter pylori infection. Methods: Catechol chitosan with mucoadhesive function was prepared by N (3 dimethylaminopropyl) N′ ethylcarbodiimide hydrochloride（EDC） catalyzed amide reaction. Then, catechol chitosan coating microcapsule with barium sulfate was obtained (Cat C/A@BS MCs) by one step electrostatic spraying and polyelectrolyte self assembly method. Mice were continuously intragastrically administered for 10 days, and their body weight changes and rapid urease test intensity were evaluated. Results: Cat C/A@BS MCs with uniform morphology and particle size about 500 μm were successfully prepared. Cat C/A@BS MCs have good CT imaging capabilities and can effectively retention in the mice digestive tract for up to 48 hours. In vivo experiments verified that Cat C/A@BS MCs effectively increased the clearance rate of Helicobacter pylori infection by amoxicilin. Conclusion: The successful constructed mucosal adhesion and CT imaging dual function microcapsules significantly improved the removal of Helicobacter pylori infection by amoxicillin.