Abstract Given the great demand for polymers prepared from renewable materials, the synthesis of a glutamic-acid-based hydrogel by solution and inverse miniemulsion polymerization is herein presented. Free radical initiated homopolymerizations of N-acryloyl- l -glutamic acid (l- AGA) resulted in either a readily water-soluble polymer or a physically cross-linked hydrogel, being the formation of physical cross-linking junctions closely related to monomer concentration and mixture viscosity. Chemically cross-linked poly( l -AGA-co-BIS) hydrogels were also synthesized by copolymerization of l -AGA and N,N′-methylenebis(acrylamide) (BIS). Both poly (l- AGA) and poly( l -AGA-co-BIS) swelling behavior were found to be pH-dependent and induced by protonation/deprotonation of the polymer three-dimensional network. Poly( l -AGA) and poly( l -AGA-co-BIS) nanogels with average sizes ranging from 280 to 370 nm (in swollen state) were further synthesized by a straightforward inverse miniemulsion polymerization and were efficiently loaded with doxorubicin. Cytotoxicity of nanogels against HeLa or L929 cells demonstrated that both poly( l -AGA) and poly( l -AGA-co-BIS) are non-toxic. The obtained results show that l -glutamic-acid-based nanogels may have a great potential in hydrophilic drug nanocarriers.

中文翻译：

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pH 响应物理和化学交联的谷氨酸基水凝胶和纳米凝胶

摘要 鉴于对由可再生材料制备的聚合物的巨大需求，本文提出了通过溶液和反相细乳液聚合合成谷氨酸基水凝胶。N-丙烯酰-l-谷氨酸（l-AGA）的自由基引发的均聚导致易溶于水的聚合物或物理交联的水凝胶，物理交联结的形成与单体浓度和混合物粘度。化学交联的聚（l-AGA-co-BIS）水凝胶还通过l-AGA和N，N'-亚甲基双（丙烯酰胺）（BIS）的共聚反应合成。发现聚 (1-AGA) 和聚 (1-AGA-co-BIS) 溶胀行为均依赖于 pH 值，并由聚合物三维网络的质子化/去质子化诱导。平均尺寸范围为 280 到 370 nm（膨胀状态）的聚（l-AGA）和聚（l-AGA-co-BIS）纳米凝胶通过直接的反相细乳液聚合进一步合成，并有效地加载了阿霉素。纳米凝胶对 HeLa 或 L929 细胞的细胞毒性表明聚 (l -AGA) 和聚 (l -AGA-co-BIS) 都是无毒的。所得结果表明，l-谷氨酸基纳米凝胶在亲水性药物纳米载体方面可能具有巨大的潜力。