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Dual-imprinted GO/TiO 2 -loaded nanocomposite membranes based on polydopamine-based and sol–gel imprinting methods were prepared for selective separation of tetracycline. [Display omitted] Molecularly imprinted membranes (MIMs) with sufficient and even-distributed recognition sites that can break the permeability-selectivity trade-off phenomenon are desirable in chemical field of selective separation. Herein graphene oxide (GO)/TiO 2 -loaded nanocomposite fibrous membranes were prepared by developing two kinds of tetracycline (TC)-imprinted systems in the same MIMs-based material. Thereinto, polydopamine-based and sol–gel-based imprinting processes were applied to the synthesis of GO/TiO 2 -loaded dual-imprinted mixed matrix membranes (GT-DIMs). The as-prepared GT-DIMs encompassed innovative GO/TiO 2 -based nanocomposite fibrous channels and two kinds of TC-imprinted systems, and critical comparisons regarding the fluxes, rebinding capacities and permselectivity were provided and studied. Importantly, dual-imprinted system of GT-DIMs could not only allow for largely enhanced rebinding result (70.63 mg/g) and fast adsorption equilibrium rate within 30 min, but also facilitate the high permselectivity of TC in complex separation systems and lab-simulated wastewater samples. The permselectivity factors were all around 5.0, which strongly demonstrated the efficiently selective recognition and separation performance of GT-DIMs. Overall, based on testing results of practical separation and scalability, excellent structural stability and separation continuity had been successfully obtained for selective separation applications of pollutants. [ABSTRACT FROM AUTHOR]

Based on the synergistic effect of the MOF mixed matrix membrane prepared by rotary evaporation and the polydopamine imprinted layer, a boronate-affinity sol–gel double-imprinted UiO-66/PVDF nanocomposite membrane was constructed. [Display omitted] • Imprinted structures based on borate affinity sol–gel dual imprinting synergy was developed. • The application of acetone and rotary evaporation technology promoted the uniform dispersion of MOF particles. • The dopamine-imprinted layer exhibited good adsorption to SA molecules. • The developed membrane achieves high performance flux and permeation selectivity. Compared to traditional separation methods, membrane-based separation can reduce environmental impact while reducing energy consumption. However, traditional adsorbents have issues with low selectivity and adsorption capacity because they enclose the majority of their functional sites in their thick structures. In this research, molecularly imprinted nanocomposite membranes were inventively integrated with boronate-affinity sol–gel imprinting technique (BSIT). It is important to note that in this work, the metal–organic frameworks (MOFs) mixed-matrix membrane (MMMs) served as the initial platform for the polydopamine (PDA)-based imprinting layer. The key to the fabrication of the MOFs MMMs was the employment of the rotary evaporation technique. The prepared boronate-affinity sol–gel molecularly imprinted membranes (BS-MIMs) played an important role in the high selectivity of the specific compound shikimic acid (SA) through covalent (boronate-affinity) and non-covalent (–OH and –NH 2) effect. This new approach provides a more precise combination of simultaneously increasing selectivity (greater than 5.0) and adsorption capacity (up to 107.87 mg g−1). The efficiency of BSIT makes it extremely competitive for the development of selective separation membranes. [ABSTRACT FROM AUTHOR]

Au/SiO 2 -pDA-based nanocomposite ovalbumin-imprinted membranes with controllable biocompatibility/selectivity were first proposed and developed for the achievements of thermo-responsive recognition ability and reversible cell adhesion/detachment. Inspired by the biomimetic modification strategy of dopamine self-polymerization technique, molecularly imprinted nanocomposite membranes (MINCMs) with thermo-responsive rebinding and separation performance were synthesized and evaluated. Herein, the Au/SiO 2 -based multilevel structure had been successfully obtained onto the polydopamine (pDA) modified membrane surfaces. Afterward, the poly(N -isopropylacrylamide)-based biomolecule-imprinted sites were adequately constructed by developing a photoinitiated atom transfer radical polymerization (pATRP) imprinting strategy using the high-biocompatible ovalbumin (Ova, pI 4.6) as template molecule. Therefore, thermo-responsive 'specific recognition sites' toward Ova were then achieved on the as-prepared MINCMs after the well-designed imprinting process. When the external temperature was set at 37 °C, excellent ovalbumin rebinding capacity (33.26 mg/g), selectivity factor (3.06) and structural stability were obtained. Importantly, as to the controllable biocompatibility research of this work, the bare glass and Ova-bound-MINCMs (the MINCMs were bound with Ova) showed basically the same cell adhesion behaviors and viability, indicating the excellent biocompatibility of the Ova-bound-MINCMs. Additionally, efficient and rapid regulation of cell adhesion/detachment on ovalbumin-bound MINCMs could be still obtained even after 10 cycles of temperature-switch process, which indicated that the as-prepared MINCMs had strong ability to work under high intensity and long continuous operation. [ABSTRACT FROM AUTHOR]

Molecularly imprinted nanocomposite membranes with C-MSNs-based imprinting structure, in which lysozyme was template molecule, was constructed based on our newly-developed synergetic synthesis strategy of the sol–gel imprinting-initiated system. [Display omitted] • LYZ-MINMs improved the problem embedding and aggregation of nanoparticles. • Uniform and dense C-MSNs layer was loaded on the doubles faces of membrane by self-assembly strategy. • Double-faced C-MSNs-based imprinting structure was constructed by the sol–gel imprinting-initiated system. • High rebinding capacity and selectivity of LYZ-MINMs were obtained simultaneously. • Well-designed bidirectional LYZ-imprinted membrane was applied as selective separation device. In recent years, the combination of membranes and nanomaterials has made remarkable progress in separation of proteins. Nevertheless, the current combination methods suffer from the drawbacks of aggregation and embedding of nanomaterials, leading to a loss of membrane performance. In present work, the lysozyme molecularly imprinted nanocomposite membranes (LYZ-MINMs) with uniform and dense carboxyl functionalized mesoporous silica nanoparticles (C-MSNs) layer were successfully prepared by a double-faced self-assembly strategy for selective separation of LYZ from chicken egg white. Notably, the resulted LYZ-MINMs exhibit both promoted hydrophilicity (36.2°) and enhanced rebinding capacity (509 mg g−1) by comparing with the MINMs designed with the blending method. The selectivity of LYZ-MINMs toward LYZ is improved by the sol–gel imprinting process, resulting in a satisfactory rebinding selectivity of 2.98, 3.22 and 3.45 for Cytochrome C , Bovine haemoglobin, and Ovalbumin, respectively. After ten cycles, the high regeneration rate (>90 %) demonstrates the potential of LYZ- MINMs for practical applications. In addition, the practicability of LYZ- MINMs further verified by utilizing diluted egg white. The work shows great promise for next-generation membranes for protein separation. [ABSTRACT FROM AUTHOR]