Surface modification of a polylactic acid nanofiber membrane by zeolitic imidazolate framework-8 from secondary growth for drug delivery

Abstract 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. Graphic abstract