Abstract Hydrogel nanocomposites incorporated with magnetic nanoparticles (MNPs) were widely researched as promising candidate for environment-responsive drug delivery, due to their unique magnetic properties and quick response to an external magnetic field. In this study, dextran-coated iron oxide nanoparticles (Fe3O4) with various particle size were prepared and embedded physically into dextran microgels formed via Schiff base reactions between aldehyded dextran and diamine in W/O inverse microemulsion, leading to a series of magnetic microgels with MNPs content of 3, 6, 9% by weight percentage. Similar superparamagnetic properties of as prepared microgels with Fe3O4 nanoparticles were proved, and their saturation magnetization increased with the increasing particle size or content of the MNPs. Antitumor drug doxorubicin (DOX) was encapsulated into the magnetic dextran microgels, and pH/magnetic field dual-responsive release profiles of DOX were demonstrated. Moreover, the release rate of DOX decreased obviously with the increasing MNPs content, probably due to the diffusion barrier for drug movement resulted from the reduced pore size of hydrogel matrix in respond to external magnetic field. These results indicate that the magnetic dextran microgels can serve as stimuli-sensitive drug delivery systems.

中文翻译：

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用于刺激响应性释放阿霉素的葡聚糖磁性微凝胶的制备

摘要 结合磁性纳米粒子 (MNPs) 的水凝胶纳米复合材料由于其独特的磁性和对外部磁场的快速响应而被广泛研究作为环境响应药物递送的有希望的候选者。本研究制备了不同粒径的葡聚糖包覆的氧化铁纳米颗粒 (Fe3O4)，并将其物理嵌入到 W/O 反相微乳液中乙醛葡聚糖与二胺的席夫碱反应形成的葡聚糖微凝胶中，形成了一系列具有磁性的磁性微凝胶。 MNPs含量为3、6、9%重量百分比。证明了制备的具有 Fe3O4 纳米颗粒的微凝胶具有类似的超顺磁性，并且它们的饱和磁化强度随着 MNP 的粒径或含量的增加而增加。抗肿瘤药物阿霉素 (DOX) 被封装到磁性葡聚糖微凝胶中，并证明了 DOX 的 pH/磁场双响应释放曲线。此外，随着 MNPs 含量的增加，DOX 的释放速率明显降低，这可能是由于水凝胶基质响应外部磁场而减小的孔径导致药物运动的扩散障碍。这些结果表明磁性葡聚糖微凝胶可以作为刺激敏感的药物递送系统。可能是由于水凝胶基质响应外部磁场而减小的孔径导致药物运动的扩散障碍。这些结果表明磁性葡聚糖微凝胶可以作为刺激敏感的药物递送系统。可能是由于水凝胶基质响应外部磁场而减小的孔径导致药物运动的扩散障碍。这些结果表明磁性葡聚糖微凝胶可以作为刺激敏感的药物递送系统。