Curcio Manuela, Diaz-Gomez Luis, Cirillo Giuseppe, Concheiro Angel, Iemma Francesca, Alvarez-Lorenzo Carmen
Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Rende, CS, Italy.
Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, R+DPharma Group (GI-1645), Facultad de Farmacia, and Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15782-Santiago de Compostela, Spain.
Eur J Pharm Biopharm. 2017 Aug;117:324-332. doi: 10.1016/j.ejpb.2017.05.002. Epub 2017 May 4.
pH/redox dual-responsive nanogels (DEX-SS) were prepared by precipitation polymerization of methacrylated dextran (DEXMA), 2-aminoethylmethacrylate (AEMA) and N,N'-bis(acryloyl)cystamine (BAC), and then loaded with methotrexate (MTX). Nanogels were spherical and exhibited homogeneous size distribution (460nm, PDI<0.30) as observed using dynamic light scattering (DLS) and scanning electron microscopy (SEM). DEX-SS were sensitive to the variations of pH and redox environment. Nanogels incubated in buffer pH 5.0 containing 10mM glutathione (GSH) synergistically increased the mean diameter and the PDI to 750nm and 0.42, respectively. In vitro release experiments were performed at pH 7.4 and 5.0 with and without GSH. The cumulative release of MTX in pH 5.0 medium with 10mMGSH was 5-fold higher than that recorded at pH 7.4 without GSH. Fibroblasts and tumor cells were used to tests the effects of blank DEX-SS and MTX@DEX-SS nanogels on cell viability. Remarkable influence of pH on nanogels internalization into HeLa cells was evidenced by means of confocal microscopy and flow cytometry.
通过甲基丙烯酸葡聚糖（DEXMA）、甲基丙烯酸2-氨基乙酯（AEMA）和N，N'-双（丙烯酰基）胱胺（BAC）的沉淀聚合制备pH/氧化还原双响应纳米凝胶（DEX-SS），然后负载甲氨蝶呤（MTX）。纳米凝胶呈球形，使用动态光散射（DLS）和扫描电子显微镜（SEM）观察到其尺寸分布均匀（460nm，PDI<0.30）。DEX-SS对pH和氧化还原环境的变化敏感。在含有10mM谷胱甘肽（GSH）的pH 5.0缓冲液中孵育的纳米凝胶分别使平均直径和PDI协同增加到750nm和0.42。在有和没有GSH的情况下，于pH 7.4和5.0进行体外释放实验。在含有10mM GSH的pH 5.0培养基中MTX的累积释放量比在没有GSH的pH 7.4时记录的累积释放量高5倍。使用成纤维细胞和肿瘤细胞测试空白DEX-SS和MTX@DEX-SS纳米凝胶对细胞活力的影响。通过共聚焦显微镜和流式细胞术证明了pH对纳米凝胶内化到HeLa细胞中的显著影响。
