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Sulfamethazine (SM2) is an antibacterial drug，which has been extensively used in human and veterinary medicine, long-term consumption of which may lead to the accumulation of sulfonamides in the body. Detection of sulfonamides often uses microbiological approaches, mass spectrometry and chromatography, which are expensive and time-consuming. Surface-enhanced Raman scattering-based immunochromatographic assay (SERS-ICA) has been recently applied in the detection. Herein, a Janus-labeled Au nanoparticle with subnanosized SiO 2 -monoclonal antibody and SERS reporter (DTNB) modified simultaneously (mAbAuNpDTNB) has been developed in a SERS-based lateral flow immunosensor, which can be used for rapid, quantitative and ultrasensitive detection of sulfamethazine residue in milk. The mAbAuNpDTNB exhibits a specific array on a paper stripe, which not only identifies sulfamethazine but also straightforwardly exposes the Raman reporter between the AuNps via self-assembly. The detection sensitivity of SERS-ICA for sulfamethazine reached 0.1 pg/mL, which was far below the previously published value by ELISA and the maximum residue limit set by the European Union. The entire SERS-ICA detection for sulfamethazine was completed within 15 min. Furthermore, high accuracy for this assay was exhibited in the spiking experiment with a recovery percentage of 88.1%–112.7%. The results demonstrated that this SERS-ICA can potentially be applied in point-of-care testing as an ultrasensitive and quantitative to semi-quantitative analytical method. [Display omitted] • A Janus-labeled Au nanoparticle (mAbAuNpDTNB) by a SERS-LFIA was reported for the detecting of Sulfamethazine in milk. • The mAbAuNpDTNB exhibits specific array on paper stripe. • The mAbAuNpDTNB recognizes Sulfamethazine and can directly expose Raman reporters between AuNps through self-assembly. • The detection of the SERS-ICA for Sulfamethazine achieved a sensitivity of 0.1 pg/mL. [ABSTRACT FROM AUTHOR]

The electrochemical splitting of water is considered to be an efficient and potential technique for producing clean hydrogen and oxygen. Although, there are lots of significant developments in composite of superior hydrogen evolution reaction (HER) or oxygen evolution reaction (OER) catalyst applied in water splitting currently, designing non-precious and low-cost bifunctional electrocatalysts with high performance is still an attractive challenging issue. In this article, we report a novel bifunctional electrocatalyst with cobalt-based nanoparticles (NPs) embedded in Zn-doped hierarchical porous three-dimension N-doped carbonization structure via an annealing process of metal organic frameworks (MOFs) connected by N-doped carbon nanotube (denoted as Co–Zn/PNC). This composite structure possesses the characteristics of more active sites, numerous mesopores and high conductivity. The resulting electrocatalyst (Co–Zn/PNC) can be used as both anode and cathode to roust the overall water splitting, getting a current density of 10 mA cm−2 at a cell voltage of 1.63 V in 1.0 M KOH electrolyte. • Co–Zn/PNC is prepared by Zn-doped ZIF-67 linked by N-doped CNT through pyrolysis. • Bifunctional electrocatalyst Co–Zn/PNC exhibits excellent HER and OER performance. • Zn doping can enhance the electrochemical performance of Co–Zn/PNC. [ABSTRACT FROM AUTHOR]

[Display omitted] • Au/Fe 3 O 4 /MIL-101(Cr) SERS substrate with high SERS performance and uniformity is prepared via a simple method. • The substrate could effectively combine the excellent adsorption ability of MOF with strong surface plasmon resonance property of gold nanoparticles, improving the sensitivity and stability of SERS detection. And this magnetic material can be gathered rapidly and availably by magnetic enrichment instead of other means, avoiding the loss or even damage of the samples. • The substrate with excellent SERS detection ability of sulfapyridine provides potential for the sensitive detection of the antibiotics residue. Fabrication of a magnetic substrate based on metal–organic frameworks (MOFs) with high sensitivity and stability for surface-enhanced Raman scattering (SERS) analysis were reported in this paper. MIL-101(Cr) nanoparticle prepared via a traditional hydrothermal reaction, which was combined with Fe 3 O 4 to synthesize the Fe 3 O 4 /MIL-101(Cr) composites. Then, the concentration of chloroauric acid and the time of reduction reaction were adjusted to acquire the optimal Au/Fe 3 O 4 /MIL-101(Cr) (AF-MIL) SERS substrate. The detection ability of the substrate can down to 10-8 mol/L for Rhodamine 6G (R6G) as probe molecule, and the relative standard deviation (RSD) is only about 4.48 %, which indicates that it possesses wonderful SERS performance and uniformity. Finally, the as-synthesized substrate has been adopted to test the trace level sulfapyridine, with its desirable detection ability can down to 10-6 mol/L. Such desirable SERS substrate with facile and effective operation holds great promise in the fast sensitive detection of the antibiotic residue and some other pollutants in environment. [ABSTRACT FROM AUTHOR]

A method for surface-enhanced Raman spectroscopy (SERS) sensing of polycyclic aromatic hydrocarbons (PAHs) is reported. Gold nanoparticles (AuNPs) decorated hydrophobic porous glycidyl methacrylate–ethylene dimethacrylate (GMA–EDMA) polymer is developed as the SERS substrate. GMA–EDMA material with porosity and permeability shows rapid and efficient adsorption of PAHs through presumed hydrophobic interaction, which brings the analytes close to the substrate. Meanwhile, the three dimensional porous morphology might benefit AuNPs distribution for high SERS enhancement. Studies on the effects of AuNPs surface coverage on the substrate and time of PAHs–substrate interaction are presented. The qualitative analysis and quantitative tendency of this method for PAHs detection are investigated with anthracene, phenanthrene and pyrene as probe molecules, showing that the characteristic fingerprint vibrational peaks of each PAH can be readily identified, and the limit of detections are 0.93 × 10 −7 , 4.5 × 10 −7 and 1.1 × 10 −7 M respectively. Moreover, the substrate exhibits high reproducibility with the relative standard deviation about 16% in spot and spot SERS intensity. Using this method for rapid screening of PAHs mixture in some water samples are performed well, which might be useful for environmental pollutions monitoring. [ABSTRACT FROM AUTHOR]