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Restricted access materials (RAMs) with adjustable selectivity was developed for the removal and detection of residual dyes for the solve problems of dye contamination. In this work, using homemade poly(4‐vinylbenzyl chloride‐co‐divinylbenzene) (PVBC/DVB) microspheres as substrate and successive two‐step surface‐initiated atom transfer radical polymerization (SI‐ATRP) as synthesis method, the two types of monomers, sodium 4‐vinylbenzene sulfonate (Nass) and styrene (St) were first grafted for constructing mixed interactions of adsorption sites, and then the hydrophilic glycidyl methacrylate (GMA) was polymerized, following by hydrolysis to construct diol groups on the external PVBC/DVB as the restricted access sites. The developed PVBC/DVB@poly(St‐co‐Nass)@poly(GMA) of adsorption properties was investigated by six dyes including methylene blue (MB), basic fuchsin (BF), acid fuchsin (AF), neutral red (NR), methyl orange (MO), and Congo red (CR), the adsorption capacities of those dyes and the removal rate for the binary mixed dye solution both rely on the ratio of St/Nass, confirming the adjustable adsorption selectivity. When PVBC/DVB@poly(St‐co‐Nass)@poly(GMA) was packed as solid phase extraction adsorbent in couple with UV–vis spectrum, it was applied to the determination of MB and BF in the water, fish and shrimp, good linearity with satisfactory recoveries for MB and BF are obtained to show the favorable practicability. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) possess an excellent ability for absorbing heavy metals, but their uneven particle size, difficult separation, and poor dispersion limit their wide application in the treatment of heavy metal pollution. In this paper, a monodisperse poly(4-allyloxybenzaldehyde- co -divinylbenzene) microsphere (denoted as PAD) was prepared with 4-allyloxybenzaldehyde as a functional monomer and divinylbenzene (DVB) as a crosslinker by one-step seed swelling polymerization. Subsequently, oxalyldihydrazide (ODH) and 2,4,6-trihydroxybenzene-1,3,5-tricarbaldehyde (Tp) were chosen as the precursors for coating the COF layer onto the surface of PAD through a one-pot method. The resulting monodisperse particles (diameter = 6.3 μm) with a core-shell structure were assigned as PAD@COF and possessed excellent dispersibility in water along with a high specific surface area of 163.8 m 2 g -1 . In isothermal and dynamic adsorption experiments, the maximum adsorption capacity of Cu 2+ reached 270.9 mg g -1 , with the adsorption amount reaching 93 mg g -1 after only 10 min. The Langmuir isothermal adsorption model and pseudo-second-order kinetic model were consistent with the adsorption process, indicating that the adsorption of Cu 2+ on PAD@COF occurred as a monolayer and that the adsorption process was controlled by chemical processes., Competing Interests: No conflict of interest exits in the submission of this manuscript, and manuscript is approved by all authors for publication. I would like to declare on behalf of my co-authors that the work described was original research that has not been published previously, and not under consideration for publication elsewhere, in whole or in part. All the authors listed have approved the manuscript that is enclosed., (This journal is © The Royal Society of Chemistry.)

Detection of florfenicol (FF) residues in animal-derived foods, as one of the most widely used antibiotics, is critically important to food safety. The fluorescent molecularly imprinted polymer (MIP) was synthesized by surface-initiated atom transfer radical polymerization technique with poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) microspheres, 4-vinylpyridine, ethylene glycol dimethacrylate, and FF as the matrix, functional monomer, crosslinker, and template molecule, respectively. Meanwhile, N-S co-doped carbon dot (CD) was synthesized with triammonium citrate and thiourea as precursors under microwave irradiation at 400 W for 2.5 min and then integrated into FF-MIP to obtain CD@FF-MIP. For comparison, non-imprinted polymer (NIP) without FF was also prepared. The adsorption capacity of CD@FF-MIP to FF reached 53.1 mg g -1 , which was higher than that of FF-MIP (34.7 mg g -1 ), whereas the adsorption capacity of NIP was only 17.3 mg g -1 . The adsorption equilibrium of three materials was reached within 50 min. Particularly, CD@FF-MIP exhibited an excellent fluorescence quenching response to FF in the concentration range of 3-50 µmol L -1 . As a result, CD@FF-MIP was successfully utilized to extract FF in milk samples, which were analyzed by high-performance liquid chromatography. The standard recoveries were 95.8%-98.2%, and the relative standard deviation was 1.6%-4.2%. The method showed the advantages of simple operation, high sensitivity, excellent selectivity, and low cost, and also demonstrated a great application prospect in food detection., (© 2024 Wiley‐VCH GmbH.)