pH/氧化还原双重响应胶束复合物制备与表征  

Preparation and characterization of pH/redox dual-responsive micelleplex

作　　者：王卉[1] 朱嘉[2] 贾莉[2] 陈大为[2] 乔明曦[2] WANG Hui;ZHU Jia;JIA Li;CHEN Dawei;QIAO Mingxi(China Pharmaceutical University,Nanjing 210009,China;School of Pharmacy,Shenyang Pharmaceutical University,Shenyang 110016,China)

机构地区：[1]中国药科大学,江苏南京210009 [2]沈阳药科大学药学院,辽宁沈阳110016

出　　处：《沈阳药科大学学报》2019年第12期1061-1068,共8页Journal of Shenyang Pharmaceutical University

基　　金：国家自然科学基金资助项目(81573372).

摘　　要：目的制备pH和氧化还原双重刺激响应型胶束复合物,并对其触发释放行为以及体外基因沉默效率进行评价。方法采用电位滴定法测定聚合物的pKa值,兔红细胞溶血性实验考察聚合物的溶血性。通过薄膜分散法制备胶束复合物,超滤离心法测定包封率。分别通过评价不同pH下聚合物的临界胶束浓度、粒径与粒径分布以及siRNA释放量的测定,考察胶束复合物的触发释放行为。采用MTT噻唑蓝法考察细胞存活率,化学发光法考察体外基因沉默效率。结果合成的聚合物pKa值约为6.8,在pH 4.0~7.4之间具有良好的缓冲能力,具有较低的溶血性和细胞毒性。制备的胶束复合物包封率均在89%以上。N/P为6的胶束复合物相较于N/P 10和15的胶束复合物,具有显著更好的触发释放作用(50.62%vs 7.72%和25.66%,P<0.05)和基因沉默效率(80.53%vs 59.06%和62.51%,P<0.05)。结论构建的低N/P胶束复合物具有良好的缓冲能力和较低毒性,可在肿瘤细胞内有效实现siRNA的触发释放,达到较高的基因沉默效率。Objective To construct a unique pH and redox potential-responsive micelleplex delivery system and to study the siRNA triggered-release and gene silencing efficiency of the micelleplexes.Methods The potentiometric titration method was used to measure the pKa value of the copolymer.The rabbit erythrocyte suspension1 was used to investigate the hemolysis of copolymer.The micelleplexes were prepared by film dispersion method and the encapsulation efficiency was determined by ultrafiltration method.The siRNA triggered release of micelleplexes in different N/P ratios were investigated by fluorescence spectro-photometry,dynamic light scattering and critical micelle concentration methods.The luciferase knowdown efficiency was determined by luminescence assays.Results The copolymer has a pKa value of 6.8 and showed good buffering capacity in the pH range of 4.0-7.4 and low hemolysis.The micelleplexes were in low toxicity with encapsulation efficiency above 89%.The micelleplexes in N/P 6 showed significantly more siRNA triggered-release(50.62%vs 7.72%and 25.66%,P<0.05)and better gene silencing efficiency(80.53%vs 59.06%and 62.51%,P<0.05).Conclusion The micelleplexes in low N/P ratio has good buffering capacity and low toxicity,and can responsively release siRNA in tumor cells,which results in high gene silencing efficiency.

关 键 词：siRNA递送 PH 氧化还原 触发释放 胶束复合物 

分 类 号：R943[医药卫生—药剂学]