Metal–organic frameworks (MOFs) materials have unique advantages such as high surface area and favorable structures in the drug delivery system. However, MOFs have the characteristics of easy aggregation and poor dispersion, which make the drug delivery not to reach the ideal effect. Developing biodegradable carrier for controlled drug delivery is still a challenging task. In this work, the zeolitic imidazolate framework-8/polylactic acid (ZIF-8/PLA) composite membranes were prepared by secondary growth method on the surface of electrospun nanofiber membrane. As the incubation time prolonged and the 2-methylimidazole (2-MIM) concentration increased, the size of ZIF-8 particles increased and the distribution of ZIF-8 became more uniform, resulting in increased the hydrophilicity and surface roughness. Furthermore, PLA/ZIF-8 nanofiber membranes had excellent pH response and drug release capacity. While only up to 40% of loaded drug was released in the buffer of pH value of 7.4, over 90% of drug was released at pH 5.5 due to the dissolution of ZIF-8 skeleton at acidic solution. It indicates that the pH-responsive PLA/ZIF-8 nanofiber membrane can be used as highly efficient drug carriers.

中文翻译：

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用于药物递送的二次生长沸石咪唑酯骨架-8对聚乳酸纳米纤维膜的表面改性

金属有机框架（MOFs）材料具有独特的优势，例如高表面积和在药物递送系统中有利的结构。然而，MOFs具有易聚集、分散性差的特点，使得药物递送达不到理想的效果。开发用于受控药物递送的可生物降解载体仍然是一项具有挑战性的任务。在这项工作中，采用二次生长法在电纺纳米纤维膜表面制备了沸石咪唑酯骨架-8/聚乳酸（ZIF-8/PLA）复合膜。随着孵育时间的延长和2-甲基咪唑（2-MIM）浓度的增加，ZIF-8颗粒的尺寸增加，ZIF-8的分布变得更加均匀，导致亲水性和表面粗糙度增加。此外，PLA/ZIF-8 纳米纤维膜具有优异的 pH 响应和药物释放能力。在 pH 值为 7.4 的缓冲液中仅释放高达 40% 的负载药物，而在 pH 5.5 时，由于 ZIF-8 骨架在酸性溶液中溶解，超过 90% 的药物释放。这表明pH响应型PLA/ZIF-8纳米纤维膜可用作高效的药物载体。