Mixed matrix nanocomposite imprinted membranes with multilevel hierarchical structure for high-efficiency selective recognition and separation: A bioinspired dual-imprinted strategy

Abstract

Mixed-matrix membranes with metal-organic frameworks (MOFs)-based dual-imprinted structure (MMM-MDIs) were prepared by choosing tetracycline (TC) as the template molecule. Polydopamine (PDA)-based TC-imprinted UiO-66 particles (PDA-TC-UiO-66) were constructed by developing a self-polymerization imprinting technique of dopamine, in which the dopamine molecule could be regarded as functional monomer and cross-linking agent in the same time. After the phase conversion membrane production, the sol-gel-based TC-imprinted structure could be then synthesized on the membrane surface. Importantly, due to the preparation of the dual-TC-imprinted structure in MMM-MDIs, high adsorption capacity (48.62 mg/g) and fast adsorption equilibrium rate (within 60 min) had been successfully achieved. Meanwhile, excellent permselectivity rates (β) of MMM-MDIs toward TC were also obtained as 6.33, 5.93 and 6.73, which demonstrated the successful synthesis of high-affinity and high-density TC-imprinted sites. Overall, based the practical selective separation and scalability analysis, we believed that the as-prepared MMM-MDIs with high-intensitive recognizability and permeability of template molecule would provide a possibility for breaking the permeability-selectivity trade-off of molecularly imprinted membrane materials.