This study aimed to investigate the ability of the novel materials D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate(TPOS) to construct pH-sensitive liposomes. TPOS was initially synthesized and characterized by TLC...This study aimed to investigate the ability of the novel materials D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate(TPOS) to construct pH-sensitive liposomes. TPOS was initially synthesized and characterized by TLC, FTIR, and ~1H-NMR. The buffering capacity of polyethylene glycol-distearoyl phosphatidylethanolamine(PEG-DSPE) and TPOS was determined by acid-base titration, and TPOS displayed a slower downtrend and gentler slope of titration curve than PEG-DSPE within pH 7.4–5.0. Studies on the in vitro drug release demonstrated that TPOS modified docetaxel(DOC) liposomes(TPOS-DOC-L) had a slower drugrelease rate at pH 7.4 similar to PEGylated-DOC liposomes(PEG-DOC-L), whereas the release rate reached approximately 86.92% ± 1.69% at pH 6.4. In vitro cellular uptake assays by microplate reader, and flow cytometry revealed that TPOS modified coumarin 6 liposomes(TPOS-C6-L) had stronger cellular uptake at pH 6.4 than that at pH 7.4( P < 0.01). Conversely, for PEGylated C6 liposomes(PEG-C6-L) and conventional C6 liposomes(C6-L), very similar cellular uptakes were exhibited at different pH values. Confocal laser scanning microscopy images showed that PEG-C6-L and C6-L were mainly located in lysosomes. By contrast, TPOS-C6-L showed broader cytoplasmic release and distribution at 4 h. MTT assay showed that the cytotoxicity of TPOS-DOC-L was similar to that of PEG-DOC-L and conventional DOC liposomes(DOC-L) at the same DOC concentration and at pH 7.4, but was much lower than those at pH 6.4 after 48 h of incubation. The apoptosis of PEG-DOC-L and DOC-L had no remarkable improvement with decreased pH from 7.4 to 6.4. Meanwhile, TPOS-DOC-Lsignificantly induced the apoptosis of HeLa cells with decreased pH. Therefore, TPOS can be a biomaterial for the construction of a pH-sensitive drug delivery system.展开更多
为延长盐酸吉西他滨(1)的半衰期、提高生物利用度,采用逆相蒸发法制备聚乙二醇1000维生素E琥珀酸酯(TPGS)修饰的1脂质体(1-LP),并考察其性质和在大鼠体内的药动学行为。结果表明,所得1-LP的粒径为(212.6±7.2)nm、z电位为(-31.1...为延长盐酸吉西他滨(1)的半衰期、提高生物利用度,采用逆相蒸发法制备聚乙二醇1000维生素E琥珀酸酯(TPGS)修饰的1脂质体(1-LP),并考察其性质和在大鼠体内的药动学行为。结果表明,所得1-LP的粒径为(212.6±7.2)nm、z电位为(-31.1±2.9)m V、包封率为(70.56±1.92)%、载药量为(7.41±0.05)%。绘制了1-LP和1水溶液在p H 7.4磷酸盐缓冲液中的体外释药曲线,并用几种常用模型拟合试验数据。结果二者的释药数据均用双指数模型拟合效果较好(R^2为0.996和0.947)。对比研究了SD大鼠尾静脉注射给予1-LP或市售1注射液后的药动学行为。血浆中的药物浓度采用HPLC法测定。所得主要药动学参数为:t_(1/2)(4.12±0.73)和(1.32±0.10)h,AUC_(0→∞)(37.57±1.09)和(9.64±0.20)mg·L·h^(-1),MRT_(0→∞)(6.06±0.28)和(1.67±0.04)h。展开更多
目的:研究维生素E琥珀酸聚乙二醇酯(Vit E TPGS)作为一种新型乳化剂在聚酸酐紫杉醇微球中的应用,以提高微球质量。方法:以熔解浓缩聚合法制备聚[1,3-双(对羧基苯氧基)丙烷-癸二酸],利用Vit E TPGS和聚乙烯醇(PVA)分别作乳化剂,通过单乳...目的:研究维生素E琥珀酸聚乙二醇酯(Vit E TPGS)作为一种新型乳化剂在聚酸酐紫杉醇微球中的应用,以提高微球质量。方法:以熔解浓缩聚合法制备聚[1,3-双(对羧基苯氧基)丙烷-癸二酸],利用Vit E TPGS和聚乙烯醇(PVA)分别作乳化剂,通过单乳化方法制备紫杉醇微球。结果:Vit E TPGS作为微球乳化剂的用量只有0.1%,低于传统乳化剂PVA的10%,载药量和包封产率提高到8.51%,89.1%,在体外释药实验中,无明显突释现象,累积释药率达到85%。结论:相比于传统的乳化剂PVA,无论是在微球的制备还是在药物的包封产率上,Vit E TPGS都是一种更加有效安全的乳化剂。展开更多
基金supported by National Natural Science Foundation of China (81102394)Natural Science Foundation of Liaoning Province (20170540575)
文摘This study aimed to investigate the ability of the novel materials D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate(TPOS) to construct pH-sensitive liposomes. TPOS was initially synthesized and characterized by TLC, FTIR, and ~1H-NMR. The buffering capacity of polyethylene glycol-distearoyl phosphatidylethanolamine(PEG-DSPE) and TPOS was determined by acid-base titration, and TPOS displayed a slower downtrend and gentler slope of titration curve than PEG-DSPE within pH 7.4–5.0. Studies on the in vitro drug release demonstrated that TPOS modified docetaxel(DOC) liposomes(TPOS-DOC-L) had a slower drugrelease rate at pH 7.4 similar to PEGylated-DOC liposomes(PEG-DOC-L), whereas the release rate reached approximately 86.92% ± 1.69% at pH 6.4. In vitro cellular uptake assays by microplate reader, and flow cytometry revealed that TPOS modified coumarin 6 liposomes(TPOS-C6-L) had stronger cellular uptake at pH 6.4 than that at pH 7.4( P < 0.01). Conversely, for PEGylated C6 liposomes(PEG-C6-L) and conventional C6 liposomes(C6-L), very similar cellular uptakes were exhibited at different pH values. Confocal laser scanning microscopy images showed that PEG-C6-L and C6-L were mainly located in lysosomes. By contrast, TPOS-C6-L showed broader cytoplasmic release and distribution at 4 h. MTT assay showed that the cytotoxicity of TPOS-DOC-L was similar to that of PEG-DOC-L and conventional DOC liposomes(DOC-L) at the same DOC concentration and at pH 7.4, but was much lower than those at pH 6.4 after 48 h of incubation. The apoptosis of PEG-DOC-L and DOC-L had no remarkable improvement with decreased pH from 7.4 to 6.4. Meanwhile, TPOS-DOC-Lsignificantly induced the apoptosis of HeLa cells with decreased pH. Therefore, TPOS can be a biomaterial for the construction of a pH-sensitive drug delivery system.
文摘为延长盐酸吉西他滨(1)的半衰期、提高生物利用度,采用逆相蒸发法制备聚乙二醇1000维生素E琥珀酸酯(TPGS)修饰的1脂质体(1-LP),并考察其性质和在大鼠体内的药动学行为。结果表明,所得1-LP的粒径为(212.6±7.2)nm、z电位为(-31.1±2.9)m V、包封率为(70.56±1.92)%、载药量为(7.41±0.05)%。绘制了1-LP和1水溶液在p H 7.4磷酸盐缓冲液中的体外释药曲线,并用几种常用模型拟合试验数据。结果二者的释药数据均用双指数模型拟合效果较好(R^2为0.996和0.947)。对比研究了SD大鼠尾静脉注射给予1-LP或市售1注射液后的药动学行为。血浆中的药物浓度采用HPLC法测定。所得主要药动学参数为:t_(1/2)(4.12±0.73)和(1.32±0.10)h,AUC_(0→∞)(37.57±1.09)和(9.64±0.20)mg·L·h^(-1),MRT_(0→∞)(6.06±0.28)和(1.67±0.04)h。
文摘目的:研究维生素E琥珀酸聚乙二醇酯(Vit E TPGS)作为一种新型乳化剂在聚酸酐紫杉醇微球中的应用,以提高微球质量。方法:以熔解浓缩聚合法制备聚[1,3-双(对羧基苯氧基)丙烷-癸二酸],利用Vit E TPGS和聚乙烯醇(PVA)分别作乳化剂,通过单乳化方法制备紫杉醇微球。结果:Vit E TPGS作为微球乳化剂的用量只有0.1%,低于传统乳化剂PVA的10%,载药量和包封产率提高到8.51%,89.1%,在体外释药实验中,无明显突释现象,累积释药率达到85%。结论:相比于传统的乳化剂PVA,无论是在微球的制备还是在药物的包封产率上,Vit E TPGS都是一种更加有效安全的乳化剂。
