双重pH敏感的聚合物-阿霉素偶联物胶束的制备与表征（英文）

Preparation and characterization of dual pH-sensitive polymer-doxorubicin conjugate micelles

为了有效抑制肿瘤生长并降低抗肿瘤药物的毒副作用,本研究设计并构建了基于阿霉素(DOX)与聚(2-乙基-2-噁唑啉)-聚乳酸(PEOz-PLA)偶联物(PEOz-PLA-imi-DOX)的双重pH敏感聚合物胶束。成功合成了DOX与pH敏感的PEOz-PLA经酸敏感的安息香亚胺键偶联的PEOz-PLA-imi-DOX,并用1H NMR和薄层色谱进行了确证,芘荧光探针法测定其临界胶束浓度为(14.84±3.85)mg/L。由PEOz-PLA-imi-DOX经薄膜水化法制备的偶联物胶束(PP-DOX-PM)的粒径约为21 nm,载药量为1.67%。体外释放实验表明,PP-DOX-PM具有随着pH的降低而释放逐渐加快的pH依赖性释放行为,说明该胶束能识别正常生理环境和胞内的pH差异,预示该胶束具有胞内快速释药的特征。此外,PP-DOX-PM保持了DOX对MDA-MB-231细胞的毒性。因此,PP-DOX-PM胶束在抗肿瘤方面具有潜在的优势。

In the present study, we designed and fabricated pH-sensitive polymeric micelles based on the conjugate of poly（2-ethyl-2-oxazoline）-poly（D,L-lactide）（PEOz-PLA） with doxorubicin（PEOz-PLA-imi-DOX） to efficiently inhibit tumor cell growth. Hence, PEOz-PLA-imi-DOX was successfully synthesized by connecting DOX to the hydrophobic end of pH-sensitive PEOz-PLA via acid cleavable benzoic imine linker and characterized by 1 H NMR spectrum and thin layer chromatography. The critical micelle concentration of PEOz-PLA-imi-DOX was determined to be（14.84±3.85） mg/L. The conjugate micelles（denoted as PP-DOX-PM） formed by PEOz-PLA-imi-DOX using film-hydration method were characterized to have a nano-scaled size of about 21 nm in diameter, and the drug loading content was 1.67%. PP-DOX-PM showed pH-dependent drug release behavior with gradually accelerated release of DOX with decrease of pH value, illustrating the micelles＇ distinguishing feature of endo/lysosomal pH from physiological pH by accelerating drug release. As anticipated, PP-DOX-PM maintained the cytotoxicity of DOX against MDA-MB-231 cells. Collectively, PP-DOX-PM might have great potential for effective suppression of tumor growth.