Selenium-Containing Polymer@Metal-Organic Frameworks Nanocomposites as an Efficient Multiresponsive Drug Delivery System

The development of efficient multiresponsive drug delivery systems (DDSs) to control drug release has been widely explored. Herein, a facile strategy is reported that enables the micelles of the selenium-containing polymer with the drug to be encapsulated in metal-organic frameworks (MOFs), which serves as multiresponsive drug release by employing the selenium-containing polymers with redox-triggered property and the MOFs with pH-triggered property in DDS. In this case, the micelles of selenium-containing polymers, as core easily disassembles in the presence of redox agents, can then release the drug in MOFs matrixes. The ZIF-8 (one type of MOFs) crystal frameworks serving as shell can collapse only under low pH conditions, and the drug can be further released. In the presence of external redox agents as well as the pH stimuli, the prepared nanocomposite (P@ZIF-8) drug system exhibits the capability of multiresponsive release of the doxorubicin (DOX) and possesses good selectivity in releasing the DOX under low pH conditions instead of normal pH conditions. In addition, the merits of P@ZIF-8 such as good biocompatibility, multiresponsive release properties, and especially the selective release properties under different pH conditions make the materials highly promising candidates for the realization of controlled drug delivery in tumor tissue systems.