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Molecularly imprinted polymers (MIPs) are typically synthesized in organic solvents, leading to poor compatibility with water, weak affinity and selectivity for target molecules in aqueous media. To address these challenges, a green and sustainable synthesis of sandwich bread-like ATP@MIP was conducted using polyethylenimide (PEI) and deep eutectic solvent (DES) as hydrophilic bi-functional monomers via layer-by-layer self-assembly on the attapulgite (ATP) carrier. The new ATP@MIP can provide a higher density of imprinting sites with more orderly and uniform distribution due to inhibiting the competitive polymerization between PEI and DES, thereby significantly enhancing recognition ability. Moreover, the ATP@MIP was synthesized in water, aligning with green chemistry principles and establishing a sustainable preparation method for MIP materials. Equipped with the remarkable merits of good water compatibility, excellent selectivity (IF=3.6), high adsorption capacity (77.6 mg g -1 ) and desirable repeatability (8 times), the as-prepared materials were used as a solid phase extraction adsorbent for efficient separation and enrichment of baicalin from Scutellariae Radix. More importantly, the recognizing performance of ATP@MIP for baicalin increased 1.40-1.69 times than other MIP materials, and its excellent specificity was demonstrated in comparison with several common commercial adsorbents (C18, HLB, MCX and SAX). Therefore, this work introduces a feasible and green strategy to synthesize water-compatible MIP materials for highly selective enrichment and separation of active components from natural products., Competing Interests: Declaration of competing interest The authors have declared that there are no conflicts of interest., (Copyright © 2025 Elsevier B.V. All rights reserved.)

Versatile molecularly imprinted polymers (MIPs) have been widely applied to various sample matrices, however, molecular recognition in aqueous media is still difficult. Stimuli-responsive MIPs have received increasing attentions due to their unique feature that the molecular recognition is regulated by specific external stimuli. Herein, water-compatible temperature and magnetic dual-responsive MIPs (WC-TMMIPs) with hydrophilic brushes were prepared via reversible addition-fragmentation chain transfer precipitation polymerization for reversible and selective recognition and extraction of bisphenol A (BPA). Transmission electron microscopy (TEM), Fourier transform infrared spectrometer (FT-IR) and vibrating sample magnetometry (VSM) as characterization methods were used to examine the successful synthesis of polymers, and the resultant WC-TMMIPs showed excellent thermosensitivity and simple rapid magnetic separation. Controlled adsorption and release of BPA by temperature regulation were investigated systematically, and the maximum adsorption and removal efficiency toward BPA in aqueous solutions were attained at 35 °C and 45 °C, respectively, as well as a good recoverability was exhibited with the precision less than 5% through five adsorption–desorption cycles. Phenolic structural analogs were tested and good recognition specificity for BPA was displayed. Accordingly, the WC-TMMIPs were employed as adsorbents for magnetic solid-phase extraction (MSPE) and packed SPE of BPA from seawater samples. Using the two modes followed by HPLC-UV determination, excellent linearity was attained in the range of 0.1–14.5 μM and 1.3–125 nM, with low detection limits of 0.02 μM and 0.18 nM, respectively. Satisfactory recoveries for spiked seawater samples were achieved ranging from 86.3–103.5% and 96.2–104.3% with RSD within 2.12–4.33%. The intelligent WC-TMMIPs combining water-compatibility, molecular recognition, magnetic separation, and temperature regulation proved potentially applicable for selective identification, controlled adsorption/release and high-efficiency enrichment/removal of trace targets in complicated aqueous media. [ABSTRACT FROM AUTHOR]

Highlights: [•] Double water compatible MIPs (DWC-MIPs) were prepared by RAFT polymerization. [•] DWC-MIPs has water compatible core with hydrophilic polymer brushes. [•] DWC-MIPs used as SPE sorbent for preconcentration four triazines with high efficiency. [•] The DWC-MIPs-SPE proves to be a highly effective cleanup and enrichment method. [Copyright &y& Elsevier]

Abstract: As a new class of synthetic receptors, molecularly imprinted polymers (MIPs) have shown great potential in many applications because of their good specific recognition ability, high stability, and easy preparation. The ultimate goal of molecular imprinting is to obtain MIPs that can be routinely used as alternatives to natural antibodies and receptors. However, the presently developed MIPs targeting small organic molecules mostly fail to show specific bindings in aqueous solutions, which is in sharp contrast to biological receptors and significantly limits their practical applications in such areas as biomimetic assays and sensors. Many efforts have been devoted to address this issue in the past two decades. In this feature article, I provide a detailed overview of the progress made in the development of water-compatible MIPs with an emphasis on our strategies to solve this challenging problem. Moreover, some still existing challenges and future prospects in this research area are also presented. [Copyright &y& Elsevier]

Abstract: A new and efficient approach to obtaining molecularly imprinted polymers (MIPs) with both pure water-compatible (i.e., applicable in the pure aqueous environments) and stimuli-responsive binding properties is described, whose proof-of-principle is demonstrated by the facile modification of the preformed MIP microspheres via surface-initiated reversible addition–fragmentation chain transfer (RAFT) polymerization of N-isopropylacrylamide (NIPAAm). The presence of poly(NIPAAm) (PNIPAAm) brushes on the obtained MIP microspheres was confirmed by FT-IR as well as the water dispersion and static contact angle experiments, and some quantitative information including the molecular weights and polydispersities of the grafted polymer brushes, the thickness of the polymer brush layers, and their grafting densities was provided. In addition, the binding properties of the ungrafted and grafted MIPs/NIPs in both methanol/water (4/1, v/v) and pure water solutions were also investigated. The introduction of PNIPAAm brushes onto the MIP microspheres has proven to significantly improve their surface hydrophilicity and impart stimuli-responsive properties to them, leading to their pure water-compatible and thermo-responsive binding properties. The application of the facile surface-grafting approach, together with the versatility of RAFT polymerization and the availability of many different functional monomers, makes the present methodology a general and promising way to prepare water-compatible and stimuli-responsive MIPs for a wide range of templates. [ABSTRACT FROM AUTHOR]

Herein, a novel method for molecularly imprinted polymers (MIPs) using methacrylic acid functionalized beta-cyclodextrin (MAA-β-CD) monomer is presented, which was designed as a potential water-compatible composite for the controlled release of atropine (ATP). The molecularly imprinted microspheres with pH-sensitive characteristics were fabricated using thermally-initiated precipitation polymerization, employing ATP as a template molecule. The effects of different compounds and concentrations of cross-linking agents were systematically investigated. Uniform microspheres were obtained when the ratio between ATP, MAA-β-CD, and trimethylolpropane trimethacrylate (TRIM) was 1:4:20 (mol/mol/mol) in polymerization system. The ATP loading equilibrium data was best suited to the Freundlich and Langmuir isotherm models. The in vitro drug release study was assessed under simulated oral administration conditions (pH 1.5 and 7.4). The potential usefulness of MIPs as drug delivery devices are much better than non-molecularly imprinted polymers (NIPs). The study shows that the prepared polymers are a pH stimuli-responsive system, which controlled the release of ATP, indicating the potential applications in the field of drug delivery. [ABSTRACT FROM AUTHOR]