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Early noninvasive screening and regression therapy for vulnerable atherosclerotic plaques remain challenging. In this study, it is aimed to develop a new approach for the active targeting of atherosclerotic plaques with nano‐agents to aid imaging and treatment. Biocompatible hyaluronic acid (HA)‐guided cerasomes are generated to selectively target CD44‐positive cells within the plaque in in vitro studies and in vivo testing in Apoe−/− mice. Rosuvastatin (RST) is encapsulated in the HA‐guided cerasome nano‐formulation to produce HA‐CC‐RST, which results in significant plaque regression as compared to treatment with the free drug. Moreover, gadodiamide‐loaded HA‐CC enhances magnetic resonance images of vulnerable plaques, thereby attaining the goal of improved simultaneous treatment and imaging. Transcriptomic analysis confirms plaque regression with HA‐CC–RST treatment, which potentially benefits from the anti‐inflammatory effect of RST. In summary, a safe and efficient nano‐formulation for the targeted delivery of active agents to atherosclerotic plaques is developed and may be applicable to other diagnostic and therapeutic agents for atherosclerosis treatment. [ABSTRACT FROM AUTHOR]

Abstract Cadmium telluride (CdTe) and iron oxide nanoparticles doped silica nanospheres were prepared by a multistep method. Iron oxide nanoparticles were first coated with silica and then modified with amino group. Thereafter, CdTe nanoparticles were assembled on the particle surfaces by their strong interaction with amino group. Finally, an outer silica shell was deposited. The final products were characterized by X-ray powder diffraction, transmission electron microscopy, vibration sample magnetometer, photoluminescence spectra, Fourier transform infrared spectra (FT-IR), and fluorescent microscopy. The characterization results showed that the final nanomaterial possessed a saturation magnetization of about 5.8 emu g−1and an emission peak at 588 nm when the excitation wavelength fixed at 380 nm.

Improving the signal-to-noise ratio (SNR) by amplifying the outputting signal or reducing nonspecific binding (NSB) are the key techniques in multiple immunoassay. Aiming at these issues, this paper presents an improved multiple indirect competitive immune surface-enhanced Raman scattering (ci-SERS) assay for the rapid screening of highly toxic rodenticides in food and biological samples, which ensured remarkable accuracy, ultra-sensitivity and reproducibility. The non-fouling polymer brush grafted magnetic beads (the MB@P-CyM) were prepared as multiple competitive recognition substrates after conjugating triplex haptens (the MB@P-CyM-hap). It was demonstrated that the particular 3D hair-like structures of P-CyM not only facilitate conjugate high-density hapten but reduce the steric hindrance from SERS probes recognition, thus enhancing SNB. On the other hand, Au nanoflowers (AuNFs) of high SERS activity were synthesized using a simple one-pot hydrazine reduction. For simultaneously detecting three highly toxic rodenticides, i.e., diphacinone (DPN), bromadiolone (BRD) and tetramine (TET), the obtained AuNFs were fabricated as a SERS-encoded nanoprobe cocktail after successively labeling mono-antibodies/Raman probes. By integrating the MB@P-CyM-hap with the SERS-encoded cocktail, a highly sensitive multiple SERS assay was achieved in less than 2 h with a limit of detection of 0.62 ng mL−1 for BRD, 0.42 ng mL−1 for TET and 1.37 ng mL−1 for DPN, respectively. The recoveries of these rodenticides in spiked food and biological samples were determined and ranged from 72 to 123%. Above all, the proposed modifications show remarkable improvements for high efficient multiple chemical toxin immunoassay. [ABSTRACT FROM AUTHOR]

Geopolymer is a porous inorganic material with a three-dimensional mesh structure, good mechanical properties, a simple preparation process (no sintering) and a low economic cost, and it is environmentally friendly. Geopolymer concrete has been widely used in the construction field, and many other studies have revealed that geopolymer will become one of the most promising inorganic materials with unique structure and properties. This paper provides a review of the development and current status of geopolymers and briefly explains the effects of material proportioning, experimental factors and activators on geopolymer performance. Because of the advantages of high specific surface area and high porosity, geopolymers could be used as adsorbent materials. This paper summarizes the research progresses of the adsorption of metal cations, anions, dyes, and gases by geopolymers, which emphasizes the geopolymer membranes in adsorption, and discusses the challenges and opportunities for the development of more efficient, sustainable and practical adsorption protocols. [ABSTRACT FROM AUTHOR]

Bipolar membranes, a new type of composite ion exchange membrane, contain an anion exchange layer, a cation exchange layer and an interface layer. The interface layer or junction is the connection between the anion and cation exchange layers. Water is dissociated into protons and hydroxide ions at the junction, which provides solutions to many challenges in the chemical, environmental and energy fields. By combining bipolar membranes with electrodialysis technology, acids and bases could be produced with low cost and high efficiency. The interface layer or junction of bipolar membranes (BPMs) is the connection between the anion and cation exchange layers, which the membrane and interface layer modification are vital for improving the performance of BPMs. This paper reviews the effect of modification of a bipolar membrane interface layer on water dissociation efficiency and voltage across the membrane, which divides into three aspects: organic materials, inorganic materials and newly designed materials with multiple components. The structure of the interface layer is also introduced on the performance of bipolar membranes. In addition, the remainder of this review discusses the challenges and opportunities for the development of more efficient, sustainable and practical bipolar membranes. [ABSTRACT FROM AUTHOR]

In this work, the surface plasmon resonance effect of metallic Ag, surface oxygen vacancies (SOVs), and Bi2MoO6 (BMO) material were rationally combined to construct new oxygen‐vacancy‐rich Ag/Bi2MoO6 (A/BMO‐SOVs) photocatalysts. Their synergistic effect on the photocatalytic degradation of phenol and 4‐nitrophenol under visible‐light irradiation (λ≥420 nm) was also investigated. TEM, EPR, and Raman spectra demonstrate the co‐existence of metallic Ag nanoparticles, surface oxygen vacancies, and Bi2MoO6 due to a controlled calcination process. The experimental results disclose that the 2 %A/BMO‐SOVs‐375 sample exhibited the highest photocatalytic activity for the degradation of both phenol and 4‐nitrophenol under visible‐light irradiation, achieving nearly 100 and 80 % removal efficiency, respectively, and demonstrated the apparent reaction rate constants (kapp) 183 and 26.5 times, respectively, higher than that of pure Bi2MoO6. The remarkable photodegradation performance of A/BMO‐SOVs for organic substances is attributed to the synergistic effect between the surface oxygen vacancies, metallic Ag nanoparticles, and Bi2MoO6, which not only improves the visible‐light response ability, but also facilitates charge separation. Thus, this work provides an effective strategy for the design and fabrication of highly efficient photocatalysts through integrating surface oxygen vacancies and the surface plasmon resonance effect of nanoparticles, which has the potential for both water treatment and air purification. Let's work together! A new oxygen‐vacancy‐rich Ag/Bi2MoO6 photocatalyst was fabricated by a reliable solvothermal process combined with an impregnation–calcination approach. The photocatalyst exhibited excellent visible‐light‐driven photocatalytic performances for both phenol and 4‐nitrophenol degradation because of a synergistic effect stemming from the integration of the individual advantages of surface oxygen vacancies (SOVs), metallic Ag nanoparticles, and Bi2MoO6 (BMO). [ABSTRACT FROM AUTHOR]

Precious metal intermetallic nanoclusters (IMNCs) are promising nanocatalysts for practical industrial applications. However, to date, the preparation of these nanoclusters has been restricted to harsh conditions, and only succeeds for a limited number of elements. This study developed a simple and efficient strategy that enables the synthesis of supported IMNCs under ambient conditions via inorganometallic coordination chemistry, specifically, by donating the Cl− ligand, a noble metal chloride (MClab−) forms a heterobimetallic ion (MxFeyClzn−) with the coordination‐unsaturated FeCl3. Upon reduction, the ordered heterobimetallic ions are simultaneously transformed into IMNCs and embedded into γ‐Fe2O3 nanosheets, which form from excess FeCl3. In addition to providing convincing spectral evidence for the structure of the heterobimetallic ions, magnetic measurements, atomic‐resolution electron microscopy, X‐ray absorption spectroscopy, and Fourier transform infrared spectroscopy of chemisorbed CO collectively confirm the successful preparation of the L10‐phased Pd3Fe IMNCs. Furthermore, this versatile method can be extended to synthesize other IMNCs, such as AuFe and PtFe, and seems to be applicable to IrFe, RhFe, RuFe, and MCo. When utilized as a heterogeneous catalyst in a Heck coupling reaction, the prepared Pd3Fe IMNCs display satisfactory activity and stability, highlighting their potential applications as advantageous catalysts. [ABSTRACT FROM AUTHOR]

Dithiocarbamate-grafted polyurethane (PU) composites were synthesized by anchoring dithiocarbamate (DTC) as a chelating agent to the polyethyleneimine-polydopamine (PE-DA)-functionalized graphene-based PU matrix (PE-DA@GB@PU), as a new adsorbent material for the recovery of Cu2+, Pb2+, and Cd2+ from industrial effluents. After leaching with acidic media to recover Cu2+, Pb2+, and Cd2+, dithiocarbamate-grafted PE-DA@GB@PU (DTC-g-PE-DA@GB@PU) was decomposed and PE-DA@GP was regenerated. The latter was used to recover Pd2+, Pt4+, and Au3+ from the copper leaching residue and anode slime. The present DTC-g-PE-DA@GB@PU and PE-DA@GB@PU composites show high adsorption performance, effective separation, and quick adsorption of the target ions. The morphologies of the composites were studied by scanning electron microscopy and their structures were investigated by Fourier transform infrared (FT-IR) spectroscopy and Raman spectroscopy. The effects of pH values, contact time, and initial metal ion concentration conditions were also studied. An adsorption mechanism was proposed and discussed in terms of the FT-IR results. [ABSTRACT FROM AUTHOR]

Highlights • Electrostatic self-assembly of CDs@MnO 2 is used to develop a new fluorescent immunoassay. • The fluorescent immunoassay has significantly high sensitivity for the detection of amantadine in chicken.. • The alkaline phosphatase-dependent fluorescent immunoassay has a great potential in food analysis. Abstract Fluorescence immunoassays are rapid, convenient and cost-effective for the sensitive quantitation of chemical contaminants in foodstuff. In this study, a competitive fluorescence ELISA was developed for the sensitive detection of amantadine (AMD) based on the alkaline phosphatase (ALP)-triggered fluorescence "turn-on" signals. As a fluorescence substrate, carbon dots (CDs) were adsorbed onto the surface of the MnO 2 nanosheets (NSs) and formed a nanoassembly of p-CDs@MnO 2 NSs which results in the fluorescence quench of CDs. The ALP labelled on antibody could catalyze the hydrolysis of the 2-phosphoascorbic acid into ascorbic acid. The latter could then reduce and decompose the MnO 2 NSs, which was accompanied by the release of CDs from the surface of MnO 2 NSs and led to the fluorescence recovery of CDs. The change of the fluorescence intensity is related to the concentration of AMD in solution and thus could be applied to detect AMD in an ALP-based ELISA system. The fluorescent ELISA showed a linear detection for AMD in the range of 0.048 ng mL−1 to 1.1 ng mL−1 with a detection limit (LOD) of 0.035 ng mL−1. The novel fluorescent ELISA shows potential for the highly sensitive detection of AMD and other analytes in food analysis. [ABSTRACT FROM AUTHOR]

• Carbon dots-encapsulated calcium carbonate nanospheres are facilely synthesized. • Hapten-labeled MNPs are prepared and used as the nano-carrier for the immunoassay. • Fluorescent immunoassay takes a short assay time and has satisfactory performance. Analytical methods with high sensitivities and short assay times are urgently required for the screening of "zero tolerance" hazardous substances in food. Herein, we propose a fluorescent immunoassay for the highly sensitive and rapid analysis of chloramphenicol (CAP) based on carbon dots (CDs)-encapsulated CaCO 3 nanospheres and magnetic nanoparticles (MNPs). The fluorescent immunoprobes were prepared by coupling the anti-CAP antibodies to carboxymethyl cellulose-functional CDs@CaCO 3 nanospheres. Chitosan-modified MNPs with "core–shell" structures were prepared and then conjugated to the CAP hapten, acting as the nano-carrier and interface for the immunoreaction. With the assistance of MNPs, the established fluorescent immunoassay achieved the sensitive detection of CAP in chicken with a limit of detection of 0.03 μg kg−1 and recoveries ranging from 83.7%–105.0%. The analysis results of the fluorescent immunoassay were evaluated by the enzyme-linked immunosorbent assay, having a correlation coefficient of 0.981. Our work provides a rapid, facile, and reliable strategy for the highly sensitive analysis of food contaminants based on "green" fluorescent nanoprobes. [ABSTRACT FROM AUTHOR]

• Duplex FRET-based immunassay is developed using the CDs and WS 2 nanosheets. • Polyamine coated blue/green emissive CDs are prepared and coupled with the haptens. • The immunoassay achieves the simultaneous detection of AMD and CAP residues. Herein, we proposed a duplex and homogeneous fluorescent immunoassay for the simultaneous detection of amantadine (AMD) and chloramphenicol (CAP) residue in chicken breast with both high sensitivity and short assay time. The immunoassay was based on the fluorescence resonance energy transfer (FRET) between hapten-labeled carbon dots (CDs) and antibody-modified WS 2 nanosheets. To achieve the duplex FRET, polyethyleneimine-functionalized blue and green emissive CDs with separated emission were synthesized via a one-pot hydrothermal method and directly coupled with the haptens of AMD and CAP, serving as the energy donors. The antibodies were modified on the surface of WS 2 nanosheets with high quenching efficiency to construct the energy acceptor. The specific immunoreaction could trigger the efficient FRET between the donors and the acceptors, causing the fluorescence quenching of CDs. The developed immunoassay was applied to simultaneously detect AMD and CAP, having the detection limit of 0.10 ng g−1 and 0.06 ng g−1, respectively. [ABSTRACT FROM AUTHOR]

Rapid screening monofluoroacetic acid (FAcOH) is responsible for preventing chemical poisoning and food safety events. Whereas surface enhanced Raman scattering (SERS) spectra is an effective tool for detecting forbidden chemicals, it is difficult to directly detect FAcOH due to its small Raman scattering cross section as well as weak adsorption on SERS substrates. In this work, the metal phenolic supramolecular networks (MPNs, i.e., the tannic acid and Fe 3+ complex) were fabricated on the commercial nanoanodic aluminum oxide film (NAAO) for assisting in situ chemical deposition highly uniform Ag nanostructure over large areas (the NAAO@AgNS). The low cost and simple fabrication process made the NAAO@AgNS a single-use consumable. For FAcOH detection, a specific derivative reaction between FAcOH and thiosalicylic acid (TSA) was introduced. By taking TSA as the Raman probe, its SERS signal attenuated constantly with the increasing amount of FAcOH. For improving quantitative accuracy, thiocyanate (SCN - ) was introduced on the NAAO@AgNS as an internal standard; thus, the characteristic peak intensity ratios associated with TSA and SCN - ( I 1035 / I 2125 ) were fitted to the concentration of FAcOH. It was demonstrated that the SERS assay achieved good sensitivity and selection toward FAcOH with the limit of quantitation (LOD) as low as 50 nmol L -1 . The NAAO@AgNS featured with highly sensitive, uniform, and consistent SERS performances could easily extend to wide SERS applications.

In this work, the surface plasmon resonance effect of metallic Ag, surface oxygen vacancies (SOVs), and Bi 2 MoO 6 (BMO) material were rationally combined to construct new oxygen-vacancy-rich Ag/Bi 2 MoO 6 (A/BMO-SOVs) photocatalysts. Their synergistic effect on the photocatalytic degradation of phenol and 4-nitrophenol under visible-light irradiation (λ≥420 nm) was also investigated. TEM, EPR, and Raman spectra demonstrate the co-existence of metallic Ag nanoparticles, surface oxygen vacancies, and Bi 2 MoO 6 due to a controlled calcination process. The experimental results disclose that the 2 %A/BMO-SOVs-375 sample exhibited the highest photocatalytic activity for the degradation of both phenol and 4-nitrophenol under visible-light irradiation, achieving nearly 100 and 80 % removal efficiency, respectively, and demonstrated the apparent reaction rate constants (k app ) 183 and 26.5 times, respectively, higher than that of pure Bi 2 MoO 6 . The remarkable photodegradation performance of A/BMO-SOVs for organic substances is attributed to the synergistic effect between the surface oxygen vacancies, metallic Ag nanoparticles, and Bi 2 MoO 6 , which not only improves the visible-light response ability, but also facilitates charge separation. Thus, this work provides an effective strategy for the design and fabrication of highly efficient photocatalysts through integrating surface oxygen vacancies and the surface plasmon resonance effect of nanoparticles, which has the potential for both water treatment and air purification., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Ricin, a highly toxic protein, is a controlled substance by both the Chemical Weapons Convention (CWC) and the Biological Weapons Convention (BWC). Therefore, fast precaution of potential ricin toxin plays an important role in national security and public safety. Herein, a simple, sensitive, and accurate visual detection of active ricin in complex samples is presented by combining magnetic affinity enrichment with a specific gold nanoparticle (AuNP) probe. In the first step, a dual-recognition magnetic absorbent was fabricated by simultaneously incorporating two different affinity ligands (concanavalin A and galactosamine) on low-foul polymer brushes grafted magnetic beads, which showed remarkable multivalent synergy binding capacity for ricin even under complex interfering environments. Subsequently, a homoadenine-constituted oligodeoxynucleotide named poly(21dA) was conjugated to AuNPs (the poly(21dA)-AuNPs), which served as a specific depurination substrate of active ricin. Coralyne can trigger the intact poly(21dA)-AuNPs aggregate by forming a non-Watson-Crick homoadenine/coralyne complex, but the poly(21dA)-AuNPs after reacting with active ricin failed to form this complex due to the loss of adenines. Based on these facts, active ricin can be detected as low as 12.5 ng mL -1 with the naked eyes. This detection strategy could be well-applied in various ricin-spiked complex matrices. The features such as ready operation, facile readout, and easy accessibility make the assay a better choice for fast on-site active ricin detection.

Here, we report an efficient and facile method for constructing plasmonic gold nanostructures with controlled morphology on a Si wafer and its use as a surface enhanced Raman scattering (SERS) reporting system for specific detection of HClO. To achieve this substrate, the core gold nanoparticles (AuNPs, ∼100 nm) with a monolayer of 4-mercaptoimidazole (MI) ligands were covalently linked to a thiol-derived Si wafer (MI-AuNPs@SH-Si). Taking advantage of the intermolecular NH···N hydrogen bond (HB) provided by the neighboring imidazole moiety, multiple satellite AuNPs (∼12 nm) decorated with both MI and a Raman reporter are assembled around the core MI-AuNPs at pH 5.0. The uniform morphology of the AuNP-based nanostructures on the Si wafer offer a high density of hot spots with good SERS performance for detecting HClO. The fast oxidation of the imidazole moieties by HClO causes HB destruction and therefore separation of the satellite AuNPs from the core AuNPs, which gives rise to SERS signal damping of the chip that is employed for HClO analysis. This simple and cost-effective method is highly selective for HClO over common interferences and several reactive oxygen/nitrogen species, and enabled rapid analysis at concentrations as low as 1.2 μmol L(-1). The present approach is applied to analyze water and human serum samples with satisfactory results.

We present here a novel conjugated aptamer-gold nanoparticle (Apt-AuNPs) fluorescent probe and its application for specific detection of recombinant human erythropoietin-α (rHuEPO-α). In this nanobiosensor, 12 nm AuNPs function as both a nano-scaffold and a nano-quencher (fluorescent energy acceptor), on the surface of which the complementary sequences are linked (as cODN-AuNPs) and pre-hybridized with carboxymethylfluorescein (FAM)-labeled anti-rHuEPO-α aptamers. Upon target protein binding, the aptamers can be released from the AuNP surface and the fluorescence signal is restored. Key variables such as the length of linker, the hybridization site and length have been designed and optimized. Full performance evaluation including sensitivity, linear range and interference substances are also described. This nanobiosensor provides a promising approach for a simple and direct quantification of rHuEPO-α concentrations as low as 0.92 nM within a few hours.

For the first time, a new multifunctional nanomaterial which combined the superparamagnetic property of iron oxide nanoparticles with the fluorescent property of morin-Al3+ complex was prepared. Iron oxide nanoparticles were first coated with SiO2 which could isolate them from the complex and the surrounding. Subsequently, Al2O3 . nH2O which provided active aluminum atom were deposited on the silica shell. Finally, morin which would react with the reactive aluminum atom was added into the reaction mixture to prepare the final multifunctional nanomaterial. The obtained product was characterized by X-ray powder diffraction, transmission electron microscopy, fourier transform infrared spectra, photoluminescence spectra, fluorescence microscopy, and vibration sample magnetometer. The characterization results showed that the final samples had an average size of 60 nm with spherical shape. The saturation magnetization of this new synthesized material was about 8.5 emu g(-1). Its excitation and emission wavelengths were 420 and 513 nm, respectively.