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Fluorescent molecularly imprinted nanoparticles have shown great promise in the field of chemical analysis or detection because of their high stability, selectivity, and sensitivity. In this work, fluorescent molecularly imprinted nanoparticles were synthesized by precipitation polymerization employing fluorescein isothiocyanate as luminescent material, which could efficiently and rapidly detect ciprofloxacin in water samples. The prepared fluorescent molecularly imprinted nanoparticles had remarkable stability and good selectivity with the method detection limit low to 4.04 nm. In addition, the fluorescent‐imprinted nanoparticles were capable of identifying the target with high detection efficiency and were applied to the detection of ciprofloxacin in aquaculture water with complex composition. All these would provide the direct monitoring of ciprofloxacin in environmental water with a promising fluorescent imprinting strategy. [ABSTRACT FROM AUTHOR]

Molecularly imprinted fluorescence sensors have shown great promise in environmental or biological monitoring and due to its high stability, selectivity and sensitivity. In this study, a fluorescence surface-imprinted sensor (SiO 2 -AF@MIPs) towards tetracycline (TC) was successfully prepared to address the shortcomings in current molecularly imprinted fluorescent sensor, such as slow response, limited detection and deteriorated performance in real complex samples. Benefited from the thin surface-imprinting layer, the SiO 2 -AF@MIPs sensors showed higher sensitivity (LOD low to 4.26 nM), rapid detection rate, reusable performance and excellent selectivity over several target competitors. Furthermore, the fluorescence sensor could efficiently detect TC in real biological samples, including tetracycline hydrochloride injection, human serum and swine urine. These results clearly demonstrated the potential value of this smart sensor nanomaterial in environmental monitoring and biological diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: An imprinted fluorescent sensor was fabricated based on SiO2 nanoparticles encapsulated with a molecularly imprinted polymer containing allyl fluorescein. High fluorine cypermethirin as template molecules, methyl methacrylate as functional monomer, and allyl fluorescein as optical materials synthesized a core‐shell fluorescent molecular imprinted sensor, which showed a high and rapid sensitivity and selectivity for the detection of τ‐fluvalinate. The sensor presented appreciable sensitivity with a limit of 13.251 nM, rapid detection that reached to equilibrium within 3 min, great linear relationship in the relevant concentration range from 0 to 150 nM, and excellent selectivity over structural analogues. In addition, the fluorescent sensor demonstrated desirable regeneration ability (eight cycling operations). The molecularly imprinted polymers ensured specificity, while the fluorescent dyes provided the stabile sensitivity. Finally, an effective application of the sensor was implemented by the detection of τ‐fluvalinate in real samples from vodka. The molecularly imprinted fluorescent sensor showed a promising potential in environmental monitoring and food safety. [ABSTRACT FROM AUTHOR]

Abstract A direct and facile "bottom-up" approach was carried out to prepare nitrogen doped graphene quantum dots (NGQDs) under hydrothermal conditions. The as-synthesized NGQDs exhibited an excellent excitation-independent upconversion and downconversion photoluminescent (PL) behavior. And further, the NGQDs/BiVO 4 composite photocatalysts were also fabricated to investigate enhanced visible-light photocatalytic performance. The addition of NGQDs in the NGQDs/BiVO 4 could improve the photocatalytic performance, and the results indicated 5.0 wt% NGQDs/BiVO 4 composites showed the optimal photocatalytic performance. The quenching of effects of different scavengers demonstrated that superoxide radical played a major role in MB degradation. A possible mechanism that NGQDs could enhance the photocatalytic performance of NGQDs/BiVO 4 composites had been also proposed. It was estimated that the photocatalytic performance of the NGQDs/BiVO 4 composites for the degradation of MB under visible light could be primarily ascribed to upconversion PL character of NGQDs and the efficient separation of photogenerated electrons and holes. [ABSTRACT FROM AUTHOR]

An ion-imprinted fluorescent polymer (referred to as CQD@SiO@IIP) is presented for recognition of lithium ion. The material is based on the use of carbon quantum dots (CQDs) and is prepared by a surface imprinting technique using benzo-15-crown-5 (B15C5) as the complexing agent, methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the crosslinker, 2,2-azobisisobutyronitrile (AIBN) as the radical initiator, and lithium ion as the template. After optimization of the detection conditions, the relative fluorescence intensity (F/F), best measured at excitation/emission wavelength of 360 nm/460 nm, varies linearly with the Li concentration in the range between 0.5 and 50 μmol·L, with a limit of detection of 16 μmol·L. Performance was compared to the non-imprinted material, and the imprinting factor is found to be 4.5. The ion-imprinted fluorescence material was applied to the determination of Li in (spiked) water samples and obtained good recoveries ranged from 102 to 111.6%. [ABSTRACT FROM AUTHOR]

The fabrication of a novel adsorbent with biomass as template is a kind of effective and economical means to prevent the accelerated phenomenon of eutrophication. In this article, lanthanum(III)-coordinated amino-functional groups (La-EDA) anchored into free-standing mesoporous silica films to capture phosphate for the first time. The as-prepared modified free-standing inorganic/organic silica films (La-EDA-MSF) presented an outstanding adsorption property towards phosphate even at solution with high concentration of competing anions. The pH result manifested that the La-EDA-MSF could effectively capture phosphate over a wide pH range between 3 and 7. The reusability experiments indicated that no apparent adsorption capacity loss was observed compared with any other adsorbents. For the practical application, the phosphate absorption in environment sample by the as-prepared films was also evaluated and 98.35% of the phosphate could be removed by La-EDA-MSF in 1 h. In addition, the mechanism of phosphate absorption by this novel inorganic/organic silica film absorbent was also proposed. In general, findings in this paper could push forward the development of novel hybrid silica film adsorbent for application in rapid and efficient phosphate adsorption from the wastewater. Image 1 • The adsorbents were templated by the biomass cellulose nanocrystals. • The grafted amino group enhanced the stability of lanthanum active sites. • The high adsorption capacity was due to the affinity between La3+ and phosphate. • The film materials were easily separated compared to the power materials. [ABSTRACT FROM AUTHOR]