The schematic representation of the route for the synthesis of SMIPs and the analysis of samples.

Estrone molecularly imprinted polymers were synthesized through the self-polymerization of dopamine on the surface of silica gels, which had the characteristics of mild polymerization conditions, simple reaction procedure and good specific recognition ability for estrone. The estrone molecularly imprinted polymers were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis and nitrogen adsorption-desorption tests. The characterization confirmed that the imprinted polymers were successfully grafted on the surface of silica gels. Through investigating the adsorption performance, the prepared estrone molecularly imprinted polymers exhibited high adsorption capacity, fast mass transfer, as well as excellent selectivity toward estrone. The estrone molecularly imprinted polymers as the solid-phase extraction adsorbent coupled with high-performance liquid chromatography was developed to determine estrone from the milk samples. The developed estrone molecularly imprinted polymer solid-phase extraction with high-performance liquid chromatography method exhibited satisfactory specificity, precision, accuracy and good linearity relationship in the range of 0.2-20 μg/mL. The developed method is simple, fast, effective and high specificity method and it provides a new method to detect the residues of estrone in animal foods.

A novel porous hybrid imprinted membrane (CP/CNT/DA-MIM) was prepared that could selectively anchor and separate target proteins from a complex matrix. CP/CNT/DA-MIM takes advantage of molecularly imprinted polymers and membranes, including the high selectivity of MIPs and the lower energy consumption and continuously separating mixtures of the membrane separation. The surface morphologies and physical/chemical properties of different membranes were investigated using FTIR, XRD, DSC, XPS and SEM. The results showed that the different molecules contained in CP/CNT/DA-MIM were homogeneous; two different sizes of imprinted cavities were observed in CP/CNT/DA-MIM that facilitate the selective anchoring property. The adsorption capacity, swelling behavior and mechanical properties of different constituent membranes were also compared. The results showed that the adhesion and nonspecific adsorption properties of the membrane were manifestly reduced by the addition of PVP. The binding capacity and adsorption selectivity of the membrane were apparently improved because of the existence of dopamine. MWCNTs obviously promoted the mechanical strength of the 2 membranes. CP/CNT/DA-MIM was successfully applied to separate bovine serum albumin from bovine blood. CP/CNT/DA-MIM is an economical, hydrophilic and eco-friendly membrane and provides a promising separation material for the large-scale continuous selective separation of target proteins from a complex matrix in commercial applications. 4 low-molecular-weight compounds. 12-14 Although several imprinting techniques for creating protein MIPs have been developed, 1,2 protein imprinting still faces challenges due to the inherent properties of proteins, including their complicated physicochemical properties, large sizes, poor solubility, sensitivity to chemical process and the limited viability in organic solvents, which is usually essential for MIP formation. 21 Chitosan (CS), which contains abundant amino and hydroxyl groups, has remarkable affinity to proteins. 22 CS is a linear hydrophilic polysaccharide derived from the deacetylation of chitin, which is one of the most plentiful natural biopolymers. CS has a relatively good film-forming ability and is eco-friendly and safe for humans and the environment. 23 Furthermore, it is a biocompatible and biodegradable material with attractive properties, including hydrophilicity, biocompatibility, nontoxicity and high permeability toward water. 24 These endow CS with a wide usage in molecular separation, wastewater treatment, packaging materials, artificial skin, cosmetics, bone substitutes, and so on. 25 Moreover, CS has been widely used as a supporter or functional monomer for the recognition and immobilization of proteins. 26,27 However, the specific adsorption of CS for target proteins is unsatisfactory because of the abundant functional groups in CS. 22 Additionally, the fragility, the uncontrollable porosity and the adhesive property of chitosan matrices limit the feasibility and practicability in membrane separation. 25 T...

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Highly selective molecularly imprinted polymers on the surface of silica gels were prepared by a sol-gel process and used as solid-phase extraction adsorbents for the specific recognition, enrichment and detection of cloxacilloic acid in cloxacillin. The obtained polymers were characterized by scanning electron microscopy, FTIR spectroscopy, nitrogen adsorption and desorption, elemental analysis and thermogravimetric analysis. The imprinted polymers not only possessed high adsorption capacity (6.5 μg/mg), but also exhibited fast adsorption kinetics (they adsorb 80% of the maximum amount within 20 min) and excellent selectivity (the imprinted factor was 3.6). A method using the imprinted polymers as solid-phase extraction adsorbents coupled with high-performance liquid chromatography was established with good specificity, linearity (r = 0.9962), precision (ranging from 0.5 to 6.7%), accuracy (ranging from 93.9 to 97.7%) and extraction recoveries (ranging from 78.8 to 89.8%). The limits of detection and quantification were 0.07 and 0.25 mg/g, respectively. This work could provide a promising method in the enrichment, extraction and detection of allergenic impurities in the manufacture, storage and application of cloxacillin.