State Key Laboratory of Natural Medicines, China Pharmaceutical University, No. 24 Tongjia Xiang, Nanjing, 210009, China.
Biomater Sci. 2017 Dec 19;6(1):125-135. doi: 10.1039/c7bm00776k.
New targeted RGD peptides obtained by solid phase peptide synthesis (SPPS) were successfully screened by Molecular Operating Environment (MOE) and used for the building of the 6-O-carboxymethyl chitosan based carrier with an active target on the surface. CRGDYC-6-O-carboxymethyl chitosan based nanoparticles (NPs) loaded with doxorubicin hydrochloride (DOX) were successfully prepared by an ionic gelation method with the carrier synthesized before. Synthesis conditions and formulation parameters were optimized by determining the characteristics of nanoparticles including the particle size and drug encapsulation efficiency. 6-O-Carboxymethyl chitosan concentration, calcium chloride concentration and calcium chloride/6-O-carboxymethyl chitosan ratio all had effects on the particle size and drug encapsulation efficiency. Nanoparticles with an average diameter of 193.4 nm, an average drug loading efficiency of up to 69.5% and an average drug loading of up to 0.395% were prepared successfully with the optimal formulation. Flow cytometry and confocal microscopy analyses showed that the cellular uptake of DOX in human breast cancer cell lines (MCF-7) was higher in the CRGDYC-modified nanoparticles compared with the unmodified nanoparticles. In vivo imaging showed that the distribution of CRGDYC-modified nanoparticles in the tumor site was higher compared with the unmodified nanoparticles. These results suggest that CRGDYC-6-O-carboxymethyl chitosan may be a promising cancer targeting carrier which can enhance the intracellular uptake and cytotoxicity of the drug-loaded nanoparticles.
通过固相肽合成（SPPS）获得的新型靶向 RGD 肽通过分子操作环境（MOE）成功筛选，并用于构建表面带有活性靶标的 6-O-羧甲基壳聚糖载体。通过以前合成的载体，成功地通过离子凝胶化方法制备了载有盐酸阿霉素（DOX）的 CRGDYC-6-O-羧甲基壳聚糖纳米粒子（NPs）。通过确定包括粒径和药物包封效率在内的纳米粒子的特性，优化了合成条件和配方参数。6-O-羧甲基壳聚糖浓度、氯化钙浓度和氯化钙/6-O-羧甲基壳聚糖的比例均对粒径和药物包封效率有影响。通过优化配方，成功制备了平均粒径为 193.4nm、平均载药效率高达 69.5%和平均载药量高达 0.395%的纳米粒子。流式细胞术和共聚焦显微镜分析表明，与未修饰的纳米粒子相比，人乳腺癌细胞系（MCF-7）中 DOX 的细胞摄取量在 CRGDYC 修饰的纳米粒子中更高。体内成像显示，与未修饰的纳米粒子相比，CRGDYC 修饰的纳米粒子在肿瘤部位的分布更高。这些结果表明，CRGDYC-6-O-羧甲基壳聚糖可能是一种有前途的癌症靶向载体，可增强载药纳米粒子的细胞内摄取和细胞毒性。
