【摘要】 采用溶剂挥发法制备盐酸乌拉地尔PLLA微球并通过SEM对其结构进行了表征,同时对微球的包封率和药物释放进行了测试。通过有机相加入乙醇或外水相加入盐的方法可以提高微球对药物的包封率。结果表明,当无水乙醇与三氯甲烷的比为1:2时,制得的微球包封率最高,达到30.52%。外水相中加入盐类电解质的方法也能提高药物的包封率。盐的加入使得盐酸乌拉地尔在外水相的溶解度降低,减少了药物向外水相的泄漏,从而提高了药物的包封率。其中KCl的加入对药物包封率的影响最大。当KCl浓度达到0.4%(mol)时,微球的包封率最高,达到35.52%。体外药物释放结果表明,PLLA微球具有明显的缓释作用,其释药动力学满足Higuchi方程。更多还原

【Abstract】 Poly(L-lactide) (PLLA) microspheres containing water-soluble urapidil hydrochloride were prepared by O/W solvent evaporation method. The surface morphology and the size of the microspheres prepared were observed by SEM. The drug loading efficiency of the prepared microspheres and the in vitro release rate of urapidil hydrochloride from micospheres were studied. It was found that the addition of ethanol in the organic phase or salts in aqueous phase can increase drug loading efficiency and result in a uniform microsphere drug distribution. When the volume ratio of ethanol added to trichloromethane is 1:2,the drug loading efficiency can reach its highest value of 30.52%. Moreover,since the solubility of the urapidil hydrochloride can be depressed by ether the common ion effect or by formation of new and less soluble drug salts,increasing the salt concentration in the aqueous phase can decrease the aqueous solubility of the drug,and addition of various electrolytes in the aqueous phase can also increase the drug loading efficiency. Among all the salt species added separately in this study,KCl can depress the drug solubility to the highest extent and result in forming microspheres with high drug loading efficiency. The highest drug loading efficiency of microspheres can reach 35.52% when KCl concentration is 0.4%(mol). The drug release study indicates that the urapidil hydrochloride-PLLA microspheres exhibit better sustained-release ability,and the in vitro release kinetics of urapidil hydrochloride-PLLA microspheres could be described by the Higuchi equation.更多还原