Zhan Shiping, Wang Jingchang, Wang Weijing, Cui Liyun, Zhao Qicheng
College of Environmental and Chemical Engineering, Dalian University Dalian China
Chemical and Environmental Protection Engineering Technology Research Center of Liaoning Province Dalian China.
RSC Adv. 2019 May 23;9(28):16167-16175. doi: 10.1039/c9ra01068h. eCollection 2019 May 20.
In this work, drug-loaded polymer microparticles were prepared by a supercritical solution impregnation (SSI) process with nitrendipine as the model drug and PLLA-PEG-PLLA as the drug carrier. The morphology, size, distribution and functional groups of the drug-loaded microparticles were characterized by scanning electron microscopy (SEM), laser particle size analyzer and fourier transform infrared analysis (FTIR). The effects of pressure, temperature and cosolvent concentration on the drug loading and release property of the microparticles prepared with and without cosolvent were investigated. The drug release kinetics of drug-loaded microparticles was studied with five models. The results indicated that the morphology of the drug-loaded polymer microparticles was not influenced by the SSI process. And the addition of ethanol cosolvent could significantly improve the drug loading of the microparticles. The most satisfied drug loading and the release properties of the microparticles were achieved under 55 °C, 13 MPa and cosolvent ethanol concentration of 3%. The drug could be released for more than 140 h. The analysis of the drug release kinetics showed that the experimental data fitted with Ritger-Peppas model were optimal. According to the release exponent value, the release process of the nitrendipine-loaded microparticles was controlled by Fickian diffusion, which can provides a theoretical basis for drug release of this type of experiment.
在本研究中，以尼群地平为模型药物，聚乳酸-聚乙二醇-聚乳酸（PLLA-PEG-PLLA）为药物载体，通过超临界溶液浸渍（SSI）法制备了载药聚合物微粒。采用扫描电子显微镜（SEM）、激光粒度分析仪和傅里叶变换红外光谱分析（FTIR）对载药微粒的形态、大小、分布及官能团进行了表征。考察了压力、温度和助溶剂浓度对添加和未添加助溶剂制备的微粒载药量及释放性能的影响。用五种模型研究了载药微粒的药物释放动力学。结果表明，超临界溶液浸渍法制备的载药聚合物微粒的形态不受该方法的影响。添加乙醇助溶剂可显著提高微粒的载药量。在55℃、13MPa和助溶剂乙醇浓度为3%的条件下，微粒的载药量和释放性能最佳。药物可释放140h以上。药物释放动力学分析表明，实验数据与Ritger-Peppas模型拟合效果最佳。根据释放指数值，载尼群地平微粒的释放过程受菲克扩散控制，可为该类实验的药物释放提供理论依据。
