Carboxymethyl chitosan (CMCS), as a water‐soluble, biocompatible, and biodegradable polymer, is an excellent carrier for a sustained drug delivery system. In this study, a amphiphilic carboxymethyl chitosan‐ursolic acid nano‐drug carrier modified by folic acid (FPCU) were prepared, and then the nano‐drug carrier wrapped another anticancer drug 10‐hydroxycamptothecin were self‐assembled into nanoparticles (FPCU/HCPT NPs). The FPCU/HCPT NPs had a suitable size, high drug loading efficiency of ursolic acid (6.4%) and 10‐hydroxycamptothecin (14.1%). The drug release study in vitro indicated that the nanoparticles have obviously sustained effect and pH sensitive behaviors, the drug release amount was higher at pH 5.5 than at pH 7.4. in vitro and in vivo study showed that the nanoparticles displayed a high antitumor efficiency to tumor cells compared with free drug. The nano delivery system as a carrier for ursolic acid (UA) and 10‐hydroxycamptothecin (HCPT) has good application prospects in cancer treatment.

中文翻译：

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叶酸修饰的羧甲基壳聚糖-熊果酸靶向纳米药物载体的合成与表征，用于递送熊果酸和10-羟基喜树碱

羧甲基壳聚糖（CMCS）是水溶性，生物相容性和可生物降解的聚合物，是持续药物输送系统的出色载体。本研究制备了一种由叶酸（FPCU）修饰的两亲性羧甲基壳聚糖-熊果酸纳米药物载体，然后将包裹另一种抗癌药物10-羟基喜树碱的纳米药物载体自组装成纳米颗粒（FPCU / HCPT NPs ）。FPCU / HCPT NP尺寸合适，熊果酸（6.4％）和10-羟基喜树碱（14.1％）的载药率高。体外药物释放研究表明，纳米颗粒具有明显的持续作用和对pH敏感的行为，pH 5.5的药物释放量高于pH 7.4的药物释放量。体外和体内研究表明，与游离药物相比，纳米颗粒对肿瘤细胞具有很高的抗肿瘤效率。纳米递送系统作为熊果酸（UA）和10-羟基喜树碱（HCPT）的载体，在癌症治疗中具有良好的应用前景。