Block copolymer polystyrene-b-poly(acrylic acid)(PS-b-PAA) was used as structural template for the synthesis of CaCO3 microparticles. Through this procedure, acid resistant hybrid CaCO3 micro- spheres were obtaine...Block copolymer polystyrene-b-poly(acrylic acid)(PS-b-PAA) was used as structural template for the synthesis of CaCO3 microparticles. Through this procedure, acid resistant hybrid CaCO3 micro- spheres were obtained. Acid resistant properties of this type of hybrid CaCO3 were studied. Size measurement shows that the acid resistant properties of the hybrid particles are different in different solutions, such as HCl, EDTA, and H2SO4 solutions.展开更多
以α-溴乙苯为引发剂,溴化亚铜为催化剂,2,2′-联吡啶为配体,二甲苯为溶剂,采用开放的溶液聚合体系,在磁力搅拌与氮气保护下,用原子转移自由基聚合ATRP(A tom T ransfer R ad ica lPo lym erization)法合成了嵌段共聚物聚苯乙烯-b-聚丙...以α-溴乙苯为引发剂,溴化亚铜为催化剂,2,2′-联吡啶为配体,二甲苯为溶剂,采用开放的溶液聚合体系,在磁力搅拌与氮气保护下,用原子转移自由基聚合ATRP(A tom T ransfer R ad ica lPo lym erization)法合成了嵌段共聚物聚苯乙烯-b-聚丙烯酸丁酯(PS t-b-PBA);用FT IR,1H-NM R,GPC等手段对活性聚合进行了确认,对嵌段共聚物进行了表征;水解PS t-b-PBA制备了两亲性嵌段共聚物苯乙烯-b-聚丙烯酸(PS t-b-PAA);采用直接溶解法配制了PS t-b-PAA在甲苯中的反胶束溶液;利用透射电镜(TEM)观察有效地考察了两亲嵌段共聚物PS t-b-PAA在甲苯溶液中的自组装行为.研究结果表明,在开放体系下也能较好地实施原子转移自由基聚合,制得窄分布的嵌段共聚物;控制两嵌段的长度可制得亲水链PAA短的两亲嵌段共聚物PS t-b-PAA,使其在甲苯中发生自组装,形成以亲水段为核,疏水段为壳的反胶束结构.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.50803055, 30872902).
文摘Block copolymer polystyrene-b-poly(acrylic acid)(PS-b-PAA) was used as structural template for the synthesis of CaCO3 microparticles. Through this procedure, acid resistant hybrid CaCO3 micro- spheres were obtained. Acid resistant properties of this type of hybrid CaCO3 were studied. Size measurement shows that the acid resistant properties of the hybrid particles are different in different solutions, such as HCl, EDTA, and H2SO4 solutions.
文摘以α-溴乙苯为引发剂,溴化亚铜为催化剂,2,2′-联吡啶为配体,二甲苯为溶剂,采用开放的溶液聚合体系,在磁力搅拌与氮气保护下,用原子转移自由基聚合ATRP(A tom T ransfer R ad ica lPo lym erization)法合成了嵌段共聚物聚苯乙烯-b-聚丙烯酸丁酯(PS t-b-PBA);用FT IR,1H-NM R,GPC等手段对活性聚合进行了确认,对嵌段共聚物进行了表征;水解PS t-b-PBA制备了两亲性嵌段共聚物苯乙烯-b-聚丙烯酸(PS t-b-PAA);采用直接溶解法配制了PS t-b-PAA在甲苯中的反胶束溶液;利用透射电镜(TEM)观察有效地考察了两亲嵌段共聚物PS t-b-PAA在甲苯溶液中的自组装行为.研究结果表明,在开放体系下也能较好地实施原子转移自由基聚合,制得窄分布的嵌段共聚物;控制两嵌段的长度可制得亲水链PAA短的两亲嵌段共聚物PS t-b-PAA,使其在甲苯中发生自组装,形成以亲水段为核,疏水段为壳的反胶束结构.
文摘本文以可降解聚合物单甲氧基聚乙二醇-聚乳酸聚乙醇酸(Me PEG-PLGA)为载体,羟基喜树碱(HCPT)为模型药物,利用SPG(Shirasu porous glass membrane)模板法,通过正交设计优化制备了彗星状MePEG-PLGA-HCPT共聚物粒子。采用动态光散射分析、扫描/透射电镜、X-射线衍射法和差示扫描量热法等研究载药粒子的粒径、zeta电位、载药量、收率、形态和HCPT的存在状态;初步评价了载药粒子的体外释药;MTT法初步考察对肝癌BEL-7402细胞的毒性作用。结果显示,最佳制备条件为:HCPT与MePEG-PLGA的质量比为1∶1,氮气压力为100 k Pa,SPG膜孔径为1.1μm;载药粒子在电镜下呈彗星状,其中头部螺旋成束,尾部为散开的纳米束;粒子的载药量可达到46.2%,收率为96.4%,zeta电位为-31.4 m V;HCPT以无定形态均匀分布于MePEG-PLGA粒子中,具有药物缓释的优点,且药物释放的速度随着载药量的增加而增大;该形貌的载药粒子相对于球形载药粒子对肝癌BEL-7402细胞的抑制作用更强,有用于肿瘤临床治疗的潜能。