Dual Factors Activated Metal-Organic Frameworks Hybrid Nanoplatform for Photoacoustic Imaging and Synergetic Photo-Chemotherapy
Metal-organic frameworks (MOFs) have attracted great interest as a smart drug delivery platform in the battle against cancer for their intriguing properties, such as high drug loading efficiency and microenvironment responsive degradation. Hence, the development of multifunctional MOFs integrating several theranostic elements is of crucial importance. In this work, we constructed a theranostic nanoplatform (DOX/Pd@ZIF-8) based on metal-organic frameworks encapsulating with 2D Pd nanosheets and DOX using an all-in-one strategy, taking the advantages of smart drug delivery function of MOFs and excellent optical property of Pd nanosheets. Polydopamine was then introduced (DOX/Pd@ZIF-8@PDA) to improve the biocompatibility. DOX/Pd@ZIF-8@PDA exhibited excellent photothermal conversion effect and optoacoustic effect due to the strong NIR light absorption of Pd nanosheets. The release of DOX exhibited pH-dependent manner and the release rates were accelerated in acidic solutions. While burst drug release in a relatively short period could be achieved upon 808 nm laser irradiation. Moreover, the potential of DOX/Pd@ZIF-8@PDA implemented as photoacoustic imaging contrast agents in vitro and in vivo were fully exploited. Thus photoacoustic imaging guided dual factors activated synergetic photo-chemo cancer therapy was successfully carried out.