毒死蜱-聚乳酸微球的制备及其性能评价

Preparation and characteristics analysis of microspheres of chlorpyrifos and polylactic acid

以毒死蜱为芯材,以生物可降解材料聚乳酸(PLA)为载体(壁材),采用溶剂挥发法制备了毒死蜱缓释微球,考察了芯壁材质量比及聚乳酸浓度对微球质量的影响。结果表明:当聚乳酸浓度增加时,载药量和包封率、粒径均随之增加;当芯壁材质量比减小(由1∶2减小至1∶5)时,微球粒径、载药量也逐渐减小;包封率在芯壁材质量比为1∶3和1∶4时分别为89.88%±1.67%和90.55%±1.86%;当芯壁材质量比小于1∶2时,微球呈光滑完整的球形。差示扫描量热检测分析证明,毒死蜱和聚乳酸能够有机地结合为一体。表明合适的芯壁材比例和聚乳酸浓度有利于提高制备微球的质量。

The sustained-release microspheres of chlorpyrifos was prepared by solvent evaporation method using biodegradable polylactic acid（PLA） as wall materials and chlorpyrifos as core materials.The effects of ratio between core materials to wall materials（chlorpyrifos weight/ PLA weight,CP value） and the concentration of PLA on the characteristics of microsphere were investigated.The results indicated that particle diameter,drug-loading rate and entrapment efficiency of microsphere increased with the increase of the concentration of PLA.The particle diameter and drug-loading rate of microsphere decreased when the CP value was decreased from 1∶2 to 1∶5.When the CP value were 1∶3 and 1∶4,the entrapment efficiency of microsphere were 89.88%±1.67% and 90.55%±1.86%,respectively.The smooth and intact microspheres of chlorpyrifos were formed when the CP value were lower than 1∶2.The differential scanning calorimetry（DSC） determination demonstrated that chlorpyrifos and PLA were combined well to form the microspheres.The results indicated that the appropriate concentration of PLA and CP value contributes to the property of the chlorpyrifos microspheres.