聚甲基丙烯酸甲酯/聚甲基丙烯酸-2-羟乙酯复合微球的合成及药物吸放性能

采用在甲基丙烯酸甲酯（MMA）悬浮聚合过程中滴加甲基丙烯酸-2-羟乙酯（HEMA）乳液聚合组分的悬浮-乳液耦合聚合方法，制备了大粒径聚甲基丙烯酸甲酯／聚甲基丙烯酸-2-羟乙酯（PMMA／PHEMA）复合微球。PMMA／PHEMA复合微球表面以HEMA乳液聚合物为主，且具有微孔结构。PMMA／PHEMA复合微球在水和苄醇中的平衡溶胀率大于PMMA微球。PMMA／PHEMA复合微球48h异丁苯丙酸负载百分比为35．6％，PMMA为27．6％。在磷酸盐缓冲液中释放时间达到360h，释放量占负载总量的82％；而PMMA微球的释放时间为216h，释放量仅占负载总量的60％。

Synthesis, Drug Absoprtion and Release Properties of Poly(methyl methacrylate)/ Poly( 2-hydroxyethyl methacrylate) Composite Microspheres

Suspension-emulsion combined polymerization(SECP) process,in which 2-hydroxyethyl methacrylate(HEMA) emulsion polymerization constituents(EPC) were drop-wisely added to methyl methacrylate(MMA) suspension polymerization system,was applied to prepare PMMA/PHEMA composite microspheres with great size.The particle morphology,swelling,drug absorption and release properties of microspheres were investigated.It is found that the composite microspheres exhibited porous structure in the surface and PHEMA latex particles coagulated on the surface of PMMA particle.The swelling ratios of PMMA/PHEMA composite microspheres in water and benzyl alcohol are larger than that of PMMA microspheres.The absorption capacity of ibuprofen on PMMA/PHEMA composite microspheres was 0.356 g/g polymer in 48h and the equilibrium release time and release percentage of ibuprofen are 360 h and 82%,respectively,while the absorption capacity of ibuprofen on PMMA microspheres is 0.276 g/g polymer,and the equilibrium release time and percentage are 216 h and 60%,respectively.