The construction of molecularly imprinted polymers on magnetic nanoparticles gives access to smart materials with dual functions of target recognition and magnetic separation. In this study, the superparamagnetic surface-molecularly imprinted nanoparticles were prepared via surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization using ofloxacin (OFX) as template for the separation of fluoroquinolones (FQs). Benefiting from the living/controlled nature of RAFT reaction, distinct core-shell structure was successfully constructed. The highly uniform nanoscale MIP layer was homogeneously grafted on the surface of RAFT agent TTCA modified Fe3O4@SiO2 nanoparticles, which favors the fast mass transfer and rapid binding kinetics. The target binding assays demonstrate the desirable adsorption capacity and imprinting efficiency of Fe3O4@MIP. High selectivity of Fe3O4@MIP toward FQs (ofloxacin, pefloxacin, enrofloxacin, norfloxacin, and gatifloxacin) was exhibited by competitive binding assay. The Fe3O4@MIP nanoparticles were successfully applied for the direct enrichment of five FQs from human urine. The spiked human urine samples were determined and the recoveries ranging from 83.1 to 103.1% were obtained with RSD of 0.8-8.2% (n = 3). This work provides a versatile approach for the fabrication of well-defined MIP on nanomaterials for the analysis of complicated biosystems.

Potato is the fourth main stable crop next to rice, wheat, and maize consumed widely all over the world. Nowadays, types of processed potato products have increased from time to time to meet the tremendous interest of consumers. Food processing factories produce many volumes of wastes as a byproduct (Charmley, Nelson, & Zvomuya, 2006; Schieber & Aranda, 2009). Peels of vegetables are the main byproduct of plant processing factories which has important organic compounds. Potato waste contains valuable chemical components like phenols which are suitable to apply in food preservation and pharmaceutical industries (Grunert, 2018;

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A mannose-functionalized poly (p-phenylene ethynylene) was rationally designed to achieve selective detection of bacteria. The polymer was constructed as a signaling unit and was modified by attaching aminoethyl mannose using the carboxylic acid group at the end of the linker. Incubation of Escherichia coli with the polymer yielded fluorescent bacteria aggregates through polyvalent interactions. The utility of the mannose functionalized polymer to detect E. coli expressing functional FimH mannose-specific lectin on their surface was also demonstrated. The sugar units displayed on the surface of the polymer retained their functional ability to interact with mannose-binding lectin. To determine the optimum binding time, we measured the fluorescence intensity of the polymer-bacteria suspension at intervals. Our results showed that binding in this system will reach an optimum level within 30 min of incubation. The polymer’s affinity for bacteria has been demonstrated and bacteria with a concentration of 103 CFU mL−1 can be detected by this system.

A highly selective and sensitive probe for the detection of hypochlorous acid (HClO) in real samples was designed and synthesized by using the specific reaction between HClO and phenyl azo group. Upon reaction with HClO, the nonfluorescent probe generated a highly fluorescent 2-(2-hydroxy-4-chlorophenyl)benzimidazole (HBI-Cl) fluorophore, which underwent the excited state intramolecular proton transfer process to give strong fluorescence turn-on. The sensing mechanism, conversion of the nonfluorescent azo moiety into the fluorescent derivative of HBI upon reaction with HClO, was verified by independent synthesis of HBI-Cl (ϕ ≈ 0.75). The theoretical computing results were in agreement with the experimental results that the azo moiety was the reactive site to realize fluorescence detection for HClO. Additionally, the probe was successfully utilized to determine HClO in tap water, exogenous HClO in HeLa cells, and endogenous HClO in MCF-7 cells with a low detection limit and cytotoxicity. Graphical abstract ᅟ.

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