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以聚碳酸亚丙酯(PPC)为壁材,聚乙烯醇-1788(PVA-1788)为连续相稳定剂,采用乳化溶剂挥发法制备了包裹毒死蜱的可降解微胶囊。测定了PVA-1788的质量分数、PPC的质量浓度以及PPC与毒死蜱的质量比对微胶囊性能的影响。采用土壤悬浊拟环境实验法评价了PPC的降解性能;通过光学显微镜(OM)、扫描电子显微镜(SEM)、广角X射线衍射(W-XRD)、激光粒度分布仪和高效液相色谱(HPLC)等表征了PPC-毒死蜱微胶囊的性能,同时采用柱层析法探讨了其缓释性能。结果表明:PPC具有生物可降解性;PVA-1788质量分数、PPC质量浓度以及PPC与毒死蜱的质量比对微胶囊的性能有显著影响,当PVA-1788的质量分数为1.0%、PPC的质量浓度为110 mg/mL,PPC与毒死蜱的质量比为1∶2时,可获得球形规整、粒径较小、包封率与载药量较高的微胶囊,其平均粒径为7.3μm,载药量为16.75%,包封率为89.34%。缓释性能研究结果表明,PPC微胶囊对毒死蜱具有明显的缓释效应,27 d的累积释药率达86.87%。
The degradable microcapsules coated with chlorpyrifos were prepared by emulsion solvent evaporation method using polyvinyl pyrrolidone (PPC) as the wall material and polyvinyl alcohol-1788 (PVA-1788) as the continuous phase stabilizer. The effects of mass fraction of PVA-1788, mass concentration of PPC and mass ratio of PPC to chlorpyrifos on microcapsule properties were determined. The degradation behavior of PPC was evaluated by the method of soil suspension and environmental simulation. The degradation of PPC was evaluated by OM, SEM, W-XRD, HPLC and HPLC ) And other characteristics of the PPC-chlorpyrifos microcapsules, while using column chromatography to explore its sustained release properties. The results showed that PPC was biodegradable. The PVA-1788, PPC and chlorpyrifos ratio had significant effects on the properties of microcapsules. When the mass fraction of PVA-1788 was 1.0%, the mass concentration of PPC Was 110 mg / mL, and the mass ratio of PPC to chlorpyrifos was 1: 2, the average particle size of microcapsules with spherical shape, smaller particle size, higher entrapment efficiency and higher drug loading was obtained. The dosage was 16.75%, the encapsulation efficiency was 89.34%. The results of sustained-release study showed that PPC microcapsules had a sustained release effect on chlorpyrifos and the cumulative release rate reached 86.87% on 27th day.