改性聚乳酸载药微球的制备及性能

Preparation and properties of drug loaded modified polylactic acid

摘要:

以尼莫地平为模型药物，聚乳酸（PLA）为载体材料，采用溶剂蒸发萃取法制备了N-乙烯基吡咯烷酮(NVP)接枝聚乳酸共聚物（PLA-g-PVP）微球，考察了聚乳酸浓度、乳化剂浓度、转速和投药比对微球的影响。采用红外光谱表征药物与载体的相互作用，扫描电镜观察微球表面形态，对不同接枝率共聚物微球的粒径、载药量、包封率及体外释放性能进行研究。结果表明，当PLA浓度为4%，乳化剂浓度3%，转速9000r/min，投药比为2：3时，不同接枝率改性聚乳酸微球形态圆整，平均粒径小于10μm，粒径分布窄，微球可连续释放14天以上，释放速率随着接枝率增大而增大。

Abstract:

The PLA grafted NVP copolymer microspheres were prepared by solvent evaporation extraction method using nimodipine as the model drug and analyzing main factors such as the PLA concentration, the emulsifier concentration, stirring speed and dosing ratio with orthogonal design. The surface morphology of the microspheres was scanned under electron microscope and formulation of microspheres was confirmed by FTIR. Characteristics of the powder partical such as mean diameter, drug loading rate and entrapment rate were evaluated comprehensively, and its in vitro release properties were studied. The results showed the copolymer microspheres were round and the surface was smooth, the average particle size were less than 10μm with narrow particle size distribution, with preparation process of 4% PLA concentration, 3% emulsifier concentration, 9000r/min stirring speed and 2/3 dosing ratio. The microspheres release of more than 14 days, and the release rate increased with the increasing graft ratio.