Dual responsive molecularly imprinted polymers based on UiO-66-DOX for selective targeting tumor cells and controlled drug release

Abstract

The preparation of synthetic drug delivery systems free of antibody modifications that can effectively recognize tumor sites and control drug delivery is essential for cancer therapy. In this study, UiO-66 metal–organic framework (MOF) modified with amino and phenylboronic acid groups was used as substrate to load the anti-cancer drug doxorubicin (DOX). Then a molecularly imprinted polymer (UiO-66-DOX@MIP) with sialic acid (SA) as the template molecule was further prepared on the surface of the synthesized nanoparticles using surface molecular imprinting technique (MIT). This polymer combines the excellent properties of UiO-66 and molecularly imprinted polymer (MIP). It was simple to prepare, economical and easy to obtain, and had a regular morphology. UiO-66-DOX@MIP containing molecularly imprinted binding sites that match the template molecule SA, could specifically recognize target tumor cells. The imprinted layer prevented drug leakage in normal body fluids while degrading and drug release under tumor microenvironment, with pH and glutathione (GSH) dual-responsive drug release properties. The UiO-66-DOX@MIP showed excellent biocompatibility and great cellular uptake efficiency to cancer cells without influence of interfering substances.