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Making the substrates form highly dense, homogeneous, and stable hotspots regions is important for the sensitive detection of surface-enhanced Raman spectroscopy (SERS). A new strategy based on solvent-induced (SI) SERS substrate to form a stable interval of the hotspot for detection was explored and the enhancement factor (EF) of our SERS substrates could reach about 1.4 × 109. By preferential adsorption of alcohol solutions by Q-Sepharose microsphere (QSS) in mixed water and alcohol solutions, the size of QSS@AuNPs was dynamically adjusted and the spacing between gold nanoparticles (AuNPs) was adjusted to keep the substrate in the optimal hotspot mode for the sensitive detection of SERS in the liquid state. As a real application case, such a SI-SERS strategy was employed to determine SCN- in saliva and a limit of detection (LOD) of about 10-10 M could be achieved.

A novel surface-enhanced Raman scattering (SERS) nanoprobe based on a reactive strategy was designed for the first time to determine the concentration of superoxide anion radical (O2˙−) produced from titanium dioxide by a UV radiation process. A limit of detection (LOD) for O2˙− of 9.0 nmol L−1 could be attained.

Prevalent contamination of water by cadmium ion (Cd2+) brings environmental risk, which threatening to human health including renal dysfunction, reduced lung capacity, and some cancers. It calls for rapid, sensitive and selective protocol to analyze Cd2+ on field. In this work, specific Raman probe is rationally designed by gold nanoparticles (AuNPs) functionalized with tripeptide glutathione (GSH) and Rhodamine 6G (R6G) (denoted as R6G/GSH/AuNPs), which is explored for indirectly determining trace Cd2+ in river water. Based on chelating interaction between GSH and Cd2+ to form tetrahedral Cd(SG)4, which trends easy detachment from R6G/GSH/AuNPs. With increasing Cd2+ concentration, the Raman probe without protection of GSH happens due aggregation and Raman signal of R6G increases correspondingly. The R6G/GSH/AuNPs-based Raman detection of Cd2+ in river water shows rapidness, excellent sensitivity, selectivity and good repeatability. Limit of detection of 10 ppb with a widely linear range of 0.5–20 ppm could be achieved. It could be perspective that such Raman probe could be extended to be used for on-site monitoring trace Cd2+ in river water system.

This study was to compare the pharmacokinetic characteristics of domestic altrenogest oral solution (DAOS) or imported altrenogest oral solution (IAOS) in healthy sows. A single administration (1 mg/kg body weight) of DAOS or IAOS was performed in sixteen healthy sows according to a two-period crossover design. Plasma concentrations of altrenogest (AT) were measured by high performance liquid chromatography coupled to a tandem mass spectrometer (HPLC-MS/MS) and the concentration-time data of AT was analyzed by WINNONLIN 5.2. It was suggested that the main pharmacokinetic parameters of DAOS and IAOS were as follows

Abnormal physiological levels of sialic acid (SA) could be used to diagnosis cancer progression stages. In this work, we describe an enzyme-assist-interference-free strategy for Raman selective determination of SA in serum. First, we assemble gold nanoparticles (Au NPs) onto the indium tin oxide glass (ITO) to construct an ITO/Au two-dimension substrate. Through modification of 4-mercaptoboric acid (4-MPBA) onto the surface of ITO/Au, the SA response plate is prepared due to the reversible esterification bond. In this strategy, a sandwich structure is rationally designed as ITO/Au/4-MPBA/SA/4-MPBA/Au to enhance the Raman scattering. The Raman detection linear concentration of SA ranged from 2.5 × 10-7 to 1.5 × 10-6 M, and a limit of detection about 1.2 × 10-7 M could be achieved. Considering the presence of glucose (Glu) in physiological fluid, we introduce glucose oxidase to remove the interference from Glu and realize the accurate determination of SA. The proposed novel Raman rapid method provides an ultrasensitive and interference-free protocol for the early diagnosis of cancer.

In this work, an eco-friendly corrosion inhibitor was synthesized by embedding 4-methyl-4H-1,2,4-triazole-3-thiol (4-MTTL) into phytic acid (IP6) micelles via heating (donated as IP6@4-MTTLx). The corrosion inhibitor, IP6@4-MTTLx microcapsules with self-healing capability, can be used for metal protection from corrosion in 3.5 wt% NaCl aqueous solution. By means of electrochemical impedance spectroscopy (EIS) and electrochemical polarization, the high inhibition performance of such micelle-based coating on the model metal of copper has been investigated, which is attributed to the synergistic effect of the 4-MTTL molecules and the IP6@4-MTTLx microcapsules. Damage to the coating by external force can be self-healed by leakage of 4-MTTL inside IP6@4-MTTLx microcapsules to seal physically and chemically the cracks. Keywords: Copper, Corrosion inhibitor, Self-healing, Phytic acid micelles, 4-Methyl-4H-1,2,4-triazole-3-thiol (4-MTTL)

To improve the service life of valve retainer in the engine exhaust system, the NiCoCrAlY alloy coating was fabricated on compacted graphite cast iron by laser cladding. Microstructure and high-temperature wear resistance of the coating were studied. The coating exhibits a refined dendritic structure. The M23C6 nano-precipitates with rod-shape are embedded the γ(Fe, Ni) solid solution dendrites, and the M7C3 nano-precipitates are distributed in the inter-dendrite region. The average nano-hardness of the coating and the substrate are measured as 4.08 GPa and 3.96 GPa, respectively. The wear morphologies and coefficient of friction variation reveal that the friction layer formed at 25°C and 600°C is a mechanical mixing layer and a composite layer, respectively. The coating possesses excellent wear resistance at 600°C due to the formation of a dense oxide film. The main component of the oxide film is identified as Fe2O3, Fe3O4, Al2O3, CrO2, CrO3 and Cr2O3.

We report a facile approach to prepare high density of tiny Pt nanoparticles less than 3 nm loaded on the polyaniline hollow tubes in uniform way. Polyaniline hollow tubes in diameter of micro size are synthesized via the polymerization of aniline onto the template of sulfonated electrospun polystyrene fibers, followed by the removal of core polystyrene fibers. The as-prepared highly crystalline Pt nanoparticles on the surface of polyaniline microtubes show the much higher electrochemical active surface area of 90.49 m2/g, high mass catalytic current density, good durability toward the methanol oxidation reaction as well as the excellent carbon monoxide tolerance. The hollow-structure-conductive-polymer- based synthesis strategy for high performance catalyst in this study could be applied to produce other catalysts with the enhanced activities.

The synthesis and spectroscopic characterization of a family of Ni-X (X = Cl, Br, I, H) complexes supported by the bulky α-diimine chelate N, N'-bis(1 R,2 R,3 R,5 S)-(-)-isopinocampheyl-2,3-butanediimine (ipcADI) are described. Diimine-supported, three-coordinate nickel(I)-X complexes have been proposed as key intermediates in a host of catalytic transformations such as C-C and C-heteroatom cross-coupling and C-H functionalization but have until now remained synthetically elusive. A combination of structural, spectroscopic, electrochemical, and computational studies were used to establish the electronic structure of each monomeric [(ipcADI)NiX] (X = Cl, Br, I) complex as a nickel(I) derivative supported by a redox-neutral α-diimine chelate. The dimeric nickel hydride, [(ipcADI)Ni(μ2-H)]2, was prepared and characterized by X-ray diffraction; however, magnetic measurements and 1H NMR spectroscopy support monomer formation at ambient temperature in THF solution. This nickel hydride was used as a precatalyst for the hydrogen isotope exchange (HIE) of C-H bonds in arenes and pharmaceuticals. By virtue of the multisite reactivity and high efficiency, the new nickel precatalyst provided unprecedented high specific activities (50-99 Ci/mmol) in radiolabeling, meeting the threshold required for radioligand binding assays. Use of air-stable and readily synthesized nickel precursor, [(ipcADI)NiBr2], broad functional group tolerance, and compatibility with polar protic solvents are additional assets of the nickel-catalyzed HIE method.

Developing detection method for trace copper ions (Cu2+) has attracted great attention since Cu2+ ions would threaten to human health, including cellular toxicity, liver damage, and neuro degenerative diseases. In this work, adding L-cysteine (L-Cys) into inositol hexaphosphate (IP6) modified Ag nanoparticles (designated as L-Cys/IP6@Ag) induces the certain aggregation of nanoparticles, resulting in increasng the surface enhanced Raman scattering (SERS) signal of rhodamine 6 G (R6 G). The presence of Cu2+ ions could be adsorbed by IP6 and the concentrated Cu2+ ions could further selectively oxide Cys molecules under certain pH value, which disperses the IP6@Ag again and decreases the SERS signal of R6 G. The linear range of determination of Cu2+ ions is from 10−5 to 10-1° M as well as a low detection concentration is of 10 pM. Furthermore, the L-Cys/IP6@Ag-R6 G-based SERS sensor has been successfully applied to detect trace Cu2+ in river water.

Malondialdehyde (MDA) is a biomarker of lipid peroxidation and intracellular oxidative stress and can also be used to monitor food freshness. However, fast, accurate and ultrasensitive detection of MDA remains a challenge. In this work, a chemical reaction tandem surface-enhanced Raman spectroscopy (SERS) method was applied for trace MDA detection by gold nanoparticles (AuNPs) enriched on the surface of Q sepharose spheres (AuNPs@QSS). After derivatization of MDA with 2-thiobarbituric acid (TBA), TBA-MDA adduct could be directly detected by SERS in the reaction media utilizing AuNPs@QSS as SERS substrate. QSS play multiple roles as AuNPs adsorbent, AuNPs carrier against aggregation in acid environment, and TBA-MDA adduct enricher. SERS detection in solution and the micro-scale homogeneous AuNPs distribution on QSS surface contribute to the improved reproducibility of the substrate. This method has a wide linear range (0.33 μM to 3.3 mM in a liquid environment), low limit of detection (∼10−10 M at dry state) and has already been applied in the direct determination of MDA in oil samples without standard addition.

Sensitive and selective detection of target analyte is very important in many fields such as commodity inspection and quality monitoring. In this work, we constructed a MIPs@AgNPs surface-enhanced Raman scattering (SERS) sensor by in-situ preparation of silver nanoparticles (AgNPs) inside molecularly imprinted polymers (MIPs) matrix for bisphenol A (BPA) detection. In-situ formed AgNPs are evenly distributed and closely packed in the matrix, which is beneficial for hot spot formation and analyte-AgNPs affinity. Our MIPs@AgNPs sensor shows good BPA selectivity against structurally related molecules such as bisphenol AF (BPAF) and diethylstilbestrol (DES). Excellent sensitivity of this MIPs@AgNPs sensor is demonstrated with the detection limit of at least 5 × 10−8 mol L−1 for BPA. This sensor is reliable for the quantitative detection of BPA in real samples, validated with results of HPLC. Regeneration of this kind of SERS sensor can be easily realized by solvent rinsing and NaBH4 reduction. Together with the advantages of ease-of-fabrication, selective recognition, sensitivity and reusability, this kind of MIPs@AgNPs SERS sensor will have a promising practical applications.

Up to date, many efforts have been done to improve the performance of surface-enhanced Raman scattering spectroscopy (SERS) substrates, but the fabrication of a stable, sensitive and uniform SERS substrate in a simple way also remains a challenge. In this work, we report a very convenient way to prepare a durable, uniform, flexible and sticky SERS substrate by dropping noble metal nanoparticles colloids on highly transparent fluorescent quantitative PCR sealing membranes, designated as HTFQ-PCR-M. HTFQ-PCR-M based SERS substrate exhibits high sensitivity, superior reproducibility, good stability and thermal stability. We apply such to directly collect thiram pesticide residues on the peel of fruit and do Raman measurement, to analyze dividually methylene blue and rhodamine B in mixture by the aid of thin layer chromatography plate via “paste and peel off” approach. Moreover, HTFQ-PCR-M based SERS substrate can keep its SERS activity at 90℃. As a perspective, HTFQ-PCR-M based SERS substrate could offer a great practical potential for on-spot identification of trace target molecules in various real samples.

Peripheral arterial disease (PAD) is an increasingly common narrowing of the peripheral arteries that can lead to lower limb ischemia, muscle weakness and gangrene. Surgical vein or arterial grafts could improve PAD, but may not be suitable in elderly patients, prompting research into less invasive approaches. Mesenchymal stem cells (MSCs) have been proposed as potential therapy, but their effectiveness and underlying mechanisms in limb ischemia are unclear. We tested the hypothesis that treatment with naive MSCs (nMSCs) or MSCs expressing CD146 (CD146+MSCs) could improve vascularity and muscle function in rat model of hind-limb ischemia. Sixteen month old Sprague-Dawley rats were randomly assigned to 4 groups: sham-operated control, ischemia, ischemia + nMSCs and ischemia+CD146+MSCs. After 4 weeks of respective treatment, rat groups were assessed for ischemic clinical score, Tarlov score, muscle capillary density, TUNEL apoptosis assay, contractile force, and vascular endothelial growth factor (VEGF) mRNA expression. CD146+MSCs showed greater CD146 mRNA expression than nMSCs. Treatment with nMSCs or CD146+MSCs improved clinical and Tarlov scores, muscle capillary density, contractile force and VEGF mRNA expression in ischemic limbs as compared to non-treated ischemia group. The improvements in muscle vascularity and function were particularly greater in ischemia+CD146+MSCs than ischemia + nMSCs group. TUNEL positive apoptotic cells were least abundant in ischemia+CD146+MSCs compared with ischemia + nMSCs and non-treated ischemia groups. Thus, MSCs particularly those expressing CD146 improve vascularity, muscle function and VEGF expression and reduce apoptosis in rat ischemic limb, and could represent a promising approach to improve angiogenesis and muscle function in PAD.

Waste rubber wood (RW) is the castoff of rubber plantation with abundant reservation but without high-value utilization. In this study, cellulose with high purity has been efficiently isolated from waste RW and further processed into cellulose nanocrystals. By means of acetylation, more hydrophobic cellulose-based products, namely acetylated rubber wood cellulose (Ac–RWC) and acetylated rubber wood cellulose nanocrystals (Ac–RW–CNC) had been attempted as reinforcing fillers for fabricating two series of PLA-based composite films via spin coating instead of currently prevailing melt compounding technique. To ensure a uniformed dispersion of fillers in PLA matrix, the addition of reinforcing filler should be equal to or less than 5% based on the film dry weight. Compared with pure PLA film, the Ac–RWC reinforced PLA composite films are more thermally stable, while the Ac–RW–CNC reinforced PLA composite films on the other hand exhibit more enhanced performance in mechanical properties and the degree of crystallinity. The highest tensile strength (55.0 MPa) and Young’s modulus (3.9 GPa) were achieved for 5%Ac–RW–CNC/PLA composite film.

Solar water evaporation is a promising and environment-friendly approach to relieve global water scarcity issues. Currently, many reports show that the voids and porous structure are beneficial to the absorption of solar energy to generate water steam. Herein, carbon nanospheres with central cavity structures are rationally designed by the one-step NaN3/fluorinated graphite deflagration method. The Na clusters derived from NaN3 deflagration are not only provided as the hollow templates but also react with fluorinated graphite to release heat, further boosting the formation of hollow carbon nanospheres (HCSs). Benefiting from the diversity of carbon nanomaterials, rough surface, unique hollow structures, and numerous micron/submicron holes, the light absorption ability, heat localization, and water supply capacity of HCSs have been significantly enhanced. Because of these advantages, the HCS-3 exhibits an excellent water evaporation efficiency of 92.7% at 1 kW m-2, which is much higher than that of carbon nanospheres, graphene oxide, and even most of the previous carbon materials. In addition, we demonstrated that the HCSs have a long-term stability and high efficiency of production of drinkable water and purifying various types of wastewater, including seawater, strong acid/alkaline water, and water containing dyes. To sum up, the deflagration synthetic technology as a facile and ultrafast process can be a new insight for future photothermal material design.

Background Tick bites severely threaten human health because they allow the transmission of many deadly pathogens, including viruses, bacteria, protozoa, and helminths. Pruritus is a leading symptom of tick bites, but its molecular and neural bases remain elusive. Objectives This study sought to discover potent drugs and targets for the specific prevention and treatment of tick bite–induced pruritus and arthropod-related itch. Methods We used live-cell calcium imaging, patch-clamp recordings, and genetic ablation and evaluated mouse behavior to investigate the molecular and neural bases of tick bite–induced pruritus. Results We found that 2 tick salivary peptides, IP defensin 1 (IPDef1) and IR defensin 2 (IRDef2), induced itch in mice. IPDef1 was further revealed to have a stronger pruritogenic potential than IRDef2 and to induce pruritus in a histamine-independent manner. IPDef1 evoked itch by activating mouse MrgprC11 and human MRGPRX1 on dorsal root ganglion neurons. IPDef1-activated MrgprC11/X1 signaling sensitized downstream ion channel TRPV1 on dorsal root ganglion neurons. Moreover, IPDef1 also activated mouse MrgprB2 and its ortholog human MRGPRX2 selectively expressed on mast cells, inducing the release of inflammatory cytokines and driving acute inflammation in mice, although mast cell activation did not contribute to oxidated IPDef1–induced itch. Conclusions Our study identifies tick salivary peptides as a new class of pruritogens that initiate itch through MrgprC11/X1-TRPV1 signaling in pruritoceptors. Our work will provide potential drug targets for the prevention and treatment of pruritus induced by the bites or stings of tick and maybe other arthropods.

Iron-nitrogen (Fe-N) co-doped carbon nanomaterials are promising catalysts for oxygen reduction reaction (ORR) with outstanding catalytic activity at low cost. Here, we demonstrate a facile bottom-up strategy to fabricate Fe, N, B co-doped bamboo-like carbon nanotubes using ionic liquid as dopant source. We show that the synergistic effect of Fe, N, B in the mesoporous carbon structure can derive excellent ORR activity, for which the FeNB/C-800 catalyst delivers an onset potential of 0.97 V (vs. reversible hydrogen electrode, RHE), a half-wave potential of 0.81 V (vs. RHE) and a high limiting current density (5.59 mA cm−2), comparable to a commercial Pt/C. The catalyst also shows good methanol tolerance as compared to Pt/C catalyst. This work highlights a bottom-up strategy for creating ternary Fe, N, B sites on carbon nanotubes using boron-containing ionic liquid precursor.

The design and fabrication of economically viable anode catalysts for the methanol oxidation reaction (MOR) have been challenging issues in direct methanol fuel cells (DMFCs) over the decades. In this work, a composite electrochemical catalyst of Pd-coupled Ag and ZnO for the possible replacement of expensive Pt catalysts in DMFCs is successfully prepared. The as-made Pd@Ag/ZnO exhibits specific activity, which is 1.8-fold, 2.8-fold, and 4.6-fold higher than that of a Pd/ZnO catalyst, 20% Pd/C catalyst and Pd black, respectively. The improvement of the catalytic mechanism is likely due to the synergistic interaction between Pd@Ag and ZnO. The density functional theory (DFT) calculation results confirm that Ag doped into Pd weakens the adsorption of CO, dramatically improving the capability to resist CO poisoning.

In the preparation of Sb-SnO2 internal layer of PbO2 electrode, the traditional thermal decomposition method has many problems, such as environmental pollution, short service life and low catalytic activity. Herein, a three-dimensional (3D) Sb doped SnO2 nanoflowers interlayer with good conductivity was prepared on the titanium substrate by the hydrothermal strategy to fabricate a novel PbO2 electrode (Ti/Sb-SnO2NFs/PbO2). Compared to the traditional PbO2 anode, a more compact and undulating 3D morphology of Ti/Sb-SnO2NFs/PbO2 electrode exhibited a higher total and inner active sites and stronger ·OH generation ability. Specifically, three typical organics, methylene blue (MB), norfloxacin (NOR) and p-dihydroxybenzene (p-DHB), were effectively degraded by the novel Ti/Sb-SnO2NFs/PbO2 electrode with economic energy consumption and the degradation mechanism of MB was also investigated. This 3D interlayer also improved the anode stability and safety with the lifetime prolonged about 2.70 times (from 30.1 h to 81.3 h). Consequently, this work offers a meaningful method to prepare PbO2 anode with high catalytic activity and good stability for wastewater treatment.

Reactive oxygen species (ROS) play an essential role in regulating various physiological functions of living organisms. Superoxide anion (O2-.), one kind of ROS, is the single-electron reduction product of oxygen molecules, which mainly exists in plants and animals, and is closely related to many inflammatory diseases. In the field of biomedicine, with the deepening understanding of superoxide anion, more and more detection methods have been developed. This review mainly introduces the detection techniques for superoxide anion in recent years.

The residual elimination of altrenogest in swine was investigated, preparing for the determination of withdrawal time. The residues of altrenogest in sebum, muscle, liver and kidney were extracted by optimized methods and further analyzed by UPLC-MS/MS. Under experimental conditions, the LOD and LOQ of altrenogest in sebum, muscle, liver and kidney were 0.5 and 1.0 μg/kg, respectively. The recoveries were in the range of 65 and 95% and the inter- and intra-RSD were less than 15%. The established method for the extraction, purification and detection of altrenogest is suitable for the determination of the residue of altrenogest in edible tissues of pigs. It was showed that altrenogest had the highest residual concentration level in liver, followed by kidney, sebum and muscle. Then withdrawal time was set at 9 days. The study provides an effective basis for elimination of altrenogest in swine.

The enhancement of the anticancer activity by disulfiram (DSF) chelated with copper (DSF/Cu2+) has been investigated recently, while the underlying molecular mechanisms still need to be fully elucidated. Chloride channel-3 (ClC-3) is over-expressed in a variety of cancers and involves multiple tumor biological events. However, whether the over-expression of ClC-3 in tumor cells affects the sensitivity of anti-tumor drugs remains unclear. Here, we showed that the involvement of ClC-3 chloride channel in the selective cytotoxicity of DSF/Cu2+ in the poorly-differentiated nasopharyngeal carcinoma. The EC50 of DSF alone and DSF/Cu2+ in activating the Cl− channel were 95.36 μM and 0.31 μM in the CNE-2Z cells, respectively. DSF/Cu2+ exhibited a positive correlation between the induction of the Cl− currents and the inhibition of cell proliferation. DSF/Cu2+ increased the ClC-3 protein expression and induced the cell apoptosis. Cl− channel blockers, NPPB and DIDS, and ClC-3 siRNA partially inhibited the cell apoptosis, and depleted the Cl− currents induced by DSF/Cu2+ in CNE-2Z cells. However, these effects could not be observed in the normal nasopharyngeal epithelium NP69-SV40 T cells. In vivo, the transplanted human nasopharyngeal carcinoma tumors size in the DSF/Cu2+ group decreased about 73.2% of those in the solvent control group. The chloride blockers partially inhibited the antitumor action of DSF/Cu2+. These data demonstrated that the selective cytotoxicity of DSF/Cu2+ may relate to its selective activation of ClC-3 Cl− channel pathways in CNE-2Z cells. ClC-3 Cl− channel can be viewed as a new and promising target for the treatment of nasopharyngeal carcinoma.

A well-dispersed SiO2@Layered hydroxide cupric benzoate (SiO2@Cu-LBMS) with a hierarchical structure have been synthesized by a facile method. The layered hydroxide cupric benzoate with a structure of layered basic metal salt (Cu-LBMS) was directly deposited on the surface of silica spheres without any blinder. The morphology of the SiO2@Cu-LBMS nano-microsphere was observed by SEM, and the reaction conditions was also discussed. In addition, the XRD patterns and FTIR spectra provide consistent evidence to the formation of SiO2@Cu-LBMS nano-microspheres. The release behavior and drug loading capability of SiO2@Cu-LBMS microspheres were also investigated by using ibuprofen, aspirin and salicylic acid as model drugs. The results indicated that the drug loading capability of SiO2@Cu-LBMS nano-microspheres was much larger than layered hydroxide cupric benzoate, and the releasing time was significantly prolonged than layered hydroxide cupric benzoate and their physical mixture.

A composite silver nanoparticle (AgNP) ink was prepared by mixing the small AgNPs (10 nm in diameter), large AgNPs (50 nm in diameter), ethylene glycol, and deionized water at a mass ratio of 4:2:3:51. By spraying a sodium hydroxide solution, the AgNP pattern printed on the polyethylene terephthalate film surface can be sintered at room temperature with a minimum electric resistivity of 12.11 μΩ·cm, 0.7 times smaller than that sintered at 150 °C. Our study confirmed that OH− ions can partially replace citrates on AgNP surfaces at room temperature, resulting in the loss of the encapsulated density of citrates. Such loss can induce the particle agglomeration, cause the sintering necks to form, and finally create the three-dimensional conductive networks. This research is of great importance to the rapid manufacturing of low-cost, low-environmental-impact and high-performance flexible printed circuits.

Diethylhexyl phthalate(DEHP) is a kind of plasticizer，which is regarded as environmental hormone due to reproductive toxicity to human body and also has the risk of breast cancer, endometrial cancer and liver cancer after long-term intake. In this work, a rapid surface enhanced Raman scattering (SERS) technique to detect the DEHP residue level in food products is developed by optimizing the synthesis of a hexakisphosphate (IP6) stabilized Au@Ag@IP6 nanoparticles. For further improvement of detection sensitivity, such SERS substrate is treated by using 1-dodecanethiol (DT) to enable its capability of capturing more DEHP molecules into the vicinity of SERS hot spots. Au@Ag@IP6/DT-based Raman protocol could analyze DEHP down to 10−8 M. By using a portable Raman system, the simple and reliable SERS method is used to on-site determine trace DEHP in real sample of energy drinks, which meets the requirement of national standard.

The fabrication of Ag nanowire (AgNW) patterns on a working substrate is a critical step to prepare flexible/stretchable electronics. The conventional method of making AgNW patterns is based on a 2-D mask, which suffers some serious drawbacks, such as low material usage, difficulty in preparing complex patterns, and susceptibility to damaged pattern edges. To overcome these drawbacks, this study proposes the use of a 3-D mask, which when combined with a vacuum filtration system, allowed efficient fabrication of complex AgNW patterns with clear edges. In addition, we controlled the microstructure of the patterned AgNW/polydimethylsiloxane (PDMS) electrodes transferred from the membrane filter, obtaining stretchable electrodes with anisotropic electrical properties. Moreover, we greatly improved the stability and reliability of the patterned electrodes in long-term stretch/release tests by developing a PDMS/AgNW/PDMS sandwich structure. Based on these improvements, robust stretchable electrodes with a stretchability of over 80% uniaxial strain and tunable gauge factors ranging from 0.07 to 520 (a much wider range than previously reported) were fabricated by optimizing the AgNW deposition density and PDMS peel-off direction. Finally, we demonstrated the applicability of the proposed method by fabricating stretchable circuits which were able to either maintain a stable resistance or sensitively monitor various human motions, revealing its tremendous potential for applications in flexible/stretchable electronics.

This study investigated the effectiveness of gelatinized starch (GS) in the removal of surface and internalized pesticide residues from basil leaves. Surface activity of GS was confirmed by surface tension and fluorescence study. Surface-enhanced Raman scattering (SERS) mapping was applied for in situ and real-time tracking of pesticides over time. Results showed that gelatinized starch has better and safer pesticide removing effect compared to commercial surfactants. Simulation study showed that starch fragment can adjust its three-dimensional conformation according to the size of the guest with ~ four repeating α-1,4-d-glucopyranose residues interacting efficiently with pesticides. However, washing by small molecular weight surfactants will lead to a "secondary contamination" due to its amphilphilic nature and small molecular size, which can escort pesticide deeper into the leaf. Due to the wide availability, easy fabrication, efficient rinsing effect and bio-safety nature, GS should be highly recommended in family practice.

Protein glycosylation plays a key role in the process of life, and the related O-GlcNAc transferase (OGT) has become a sweet new target for cancer diagnosis and therapy. Herein, based on protease-protection strategy combining with the well-designed surface-enhanced Raman scattering (SERS) tags, a sensitive SERS assay was developed for specifically OGT activity determination. In the assay, a peptide containing both glycosylation and protease sites was designed. The two ends of the peptide are biotin and cysteine residues. Therefore, the SERS tags and the magnetic bead can be connected to the two ends of the peptide through Ag-S bond and affinity interaction, respectively. Peptide glycosylation occurs in the presence of OGT, which will protect the peptide from the next cleavage by proteinase K, and more SERS tags left in the surface of magnetic beads will contribute a high SERS signal. The SERS intensity was identified to be correlate with the activity of OGT during the measurement, and the minimum detection concentration of OGT down to 0.1 nmol/L was achieved with a wide linearity range from 10−10 to 10-7 mol/L. The inhibition assay and serum sample detection confirmed the feasibility of the SERS assay in practical application, which is essential for drug development and clinical diagnosis.

Creatinine level in urine is an important biomarker for renal function diseases, such as renal failure, glomerulonephritis, and chronic nephritis. The Au@MIL-101(Fe) was prepared by in situ growth of Au nanoparticles in MIL-101(Fe) as a selective SERS substrate. The Au@MIL-101(Fe) offers the great local surface plasmon resonance (SPR) effect due to gold nanoparticles aggregation inside metal-organic frameworks. The framework structure could enrich trace target samples and drag them into SPR hot spots. The optimal Au@MIL-101(Fe) composite substrate is used for analyzing creatinine in urine and the limit of detection is down to 0.1[Formula: see text][Formula: see text]mol/L and a linear relationship is ranging from 1[Formula: see text][Formula: see text]mol/L to 100[Formula: see text][Formula: see text]mol/L.

Parathion-methyl (PTM) as one of organophosphate insecticides was once widely used to control pests on rice, cotton and other crops. Recently, due to high toxicity to people, PTM has been prohibited in vegetable and fruit production process but illegal abuse of PTM occasionally happens in some areas. Conventional detection methods for PTM suffer from cumbersome sample pretreatment or insufficient sensitivity. In this work, we rationally prepare metal organic framework MIL-101 decorated with Au nanoparticles and cysteine modified Fe3O4 (designated as /Cys-Fe3O4/MIL-101) as magnetic surface enhanced Raman scattering (SERS) substrate. Benefiting the magnetically induced improvement effect, by using Au/Cys-Fe3O4/MIL-101, the SERS method exhibits superior sensitivity and detection reproducibility, which is successfully used to detect PTM residue in juice. The limit of detection for PTM at 5 ppb in juice is reached with a good linearity ranging from 10−11 to 10-7 M, meeting the requirement of the European Union Standard.

Epithelial ovarian cancers (EOC) present as malignant tumors with high mortality in the female reproductive system diseases. Acquired resistance to paclitaxel (PTX), one of the first-line treatment of EOC, remains a therapeutic challenge. ClC-3, a member of the voltage-gated Cl- channels, plays an essential role in a variety of cellular activities, including chemotherapeutic resistance. Here, we demonstrated that the protein expression and channel function of ClC-3 was upregulated in PTX resistance A2780/PTX cells compared with its parental A2780 cells. The silence of ClC-3 expression by siRNA in A2780/PTX cells partly recovered the PTX sensitivity through restored the G2/M arrest and resumed the chloride channel blocked. ClC-3 siRNA both inhibited the expression of ClC-3 and β-tubulin, whereas the β-tubulin siRNA reduced the expression of itself only, without affecting the expression of ClC-3. Moreover, treatment of ClC-3 siRNA in A2780/PTX cells increased the polymerization ratio of β-tubulin, and the possibility of proteins interaction between ClC-3 and β-tubulin was existing. Take together, the over-expression of ClC-3 protein in PTX-resistance ovarian cancer cells promotes the combination of ClC-3 and β-tubulin, which in turn increase the ration of free form and decrease the quota of the polymeric form of β-tubulin, and finally reduce the sensitivity to PTX. Our findings elucidated a novel function of ClC-3 in regulating PTX resistance and ClC-3 could serve as a potential target to overcome the PTX resistance ovarian cancer.

We successfully synthesized raspberry-like polydopamine/silver nanoparticles (PDA@AgNPs) composites utilizing PDA sphere as a template, a chelating agent and a binding/reducing agent. The surface enhanced Raman scattering (SERS) performance of PDA@AgNPs composites were optimized by tuning the mass of silver precursor and the reaction temperature. Acrylamide (AAm), a “potential carcinogen to human”, was employed as a model compound to validate the SERS effect of the fabricated substrate. Such PDA@AgNPs based SERS method had a wide linear range from 0.1 to 1000 μg/L and the LOD was 0.04 μg/L, lower than the maximal residual limit (0.5 μg/L in drinking water) issued by the World Health Organization. This kind of PDA@AgNPs substrate could be developed into a promising assay for on-field SERS detection with the help of portable Raman equipment.

Abuse of thiocyanate (SCN−) in food products results in the people’s health risks. Detection of SCN− residue in milk and infant formula calls for rapid and sensitive analytical protocols. In this work, Au nanoparticles dotted magnetic sheets (Au-MGS) with the help of inositol hexakisphosphate (IP6) were used as surface enhanced Raman scattering (SERS) substrate for sensitively detecting trace SCN− in milk. Since IP6 served as binding and stable agent to chelate with metal ions, the Au-MGS represented uniformity and stability as well as the well-dispersive Au nanoparticles. As a result, the limit of detection (LOD) reached 10−8 g/L. Additionally, with aiding by an external magnet inducing, Au-MGS substrate further presented improved SERS activity. By using a portable Raman spectrometer, such Au-MGS based SERS assay could be expected to be used for in situ detection of SCN− in milk on markets as well as for determination of SCN− in saliva from the smoker.

Chlorpyrifos, one of the broad-spectrum organophosphorus insecticides, is utilized extensively in agriculture. However, chlorpyrifos residues in food and water pose potential risks to human health. In this work, popcorn-like gold nanoparticles were synthesized under mild condition without any surfactant as template and serviced as SERS-active substrate for sensing chlorpyrifos by using a portable Raman spectrometer. The obtained substrate had extremely low background signal and remarkably enhanced SERS signal for detecting trace chlorpyrifos residues in fruit samples due to the “hot spots” formed between tips of gold nanopopcorns. As a result, the portable SERS-sensor system had a limit of detection at 1 μM of chlorpyrifos, which met the requirement of national standard.

A net-bracket built out from the core@shell structure of chemically oxidized polypyrrole (PPy) coated electrospun polycaprolactone (PCL) nanofibers, and the following surface modification of a thin layer of positively charged poly(dimethyl diallyl ammonium chloride) (PDDA) has been applied for stretching the reduced graphene oxide (RGO) sheets to some extent with the electrochemical deposition method. The as-formed RGO/PDDA/PCL@PPy nanocomposites were investigated by using scanning electron microscopy, transmission electron microscope, X-ray diffraction and Raman spectroscopy. The graphene tented by the net-bracket showed remarkable electrocatalytic properties in detecting the neurotransmitter dopamine (DA). Low detection limit of 0.34 μM (S/N = 3) with the wide linear detection range from 4 μM to 690 μM was obtained. The successful determination of DA in real urine samples and DA injection were achieved. Such attractive fabrication strategy can be extended to make other graphene sheet-based sensors.

Alumina is widely recognized as chemically inert, and resistant to oxidation and high temperature. In this study, Au/Al2O3 nanocomposites (NCs) were prepared by a facile method and were used as a surface enhanced Raman scattering (SERS) substrate for detection of adenosine triphosphate (ATP). This Au/Al2O3-based SERS substrate demonstrated good sensitivity with the lowest detectable concentration of 5 × 10−9 M for ATP and a good linear relationship ranging from 5 × 10−5 to 5 × 10−9 M. The strategy of improvement of SERS detection sensitivity for ATP was based on the consideration of ATP captured by such SERS substrate via chelation of aluminum and phosphates, which was validated by X-ray photoelectron spectroscopy. In addition, alumina as a supporting material could be expected to prolong the stability of such a SERS substrate.

In this paper, a two-step method is used to prepare a regenerative three-dimensional (3D) ZnO/Ag@Au substrate for developing a superior sensitive surface enhanced Raman scattering (SERS) method for detecting antibiotics. A great electromagnetic enhancement is observed from the as-prepared composite substrate, which is triggered by tuning the electron distribution of metals and semiconductor metal oxide. The strong interaction between target sample and the huge surface area of ZnO/Ag@Au composite promotes the charge transfer to produce promising chemical enhancement. The synergistic physical and chemical enhancement mechanisms are validated by density functional theory and finite difference time domain simulation. Additionally, the presence of light "echo effect" in the 3D structure of ZnO support could also amplify the efficiency of light excitation for Raman scattering. The above-stated merits benefit to boost the Raman scattering detection sensitivity for real samples. The ZnO/Ag@Au-based SERS substrate could detect rhodamine 6G molecules with an enhancement factor of up to 1.48 × 109 and the lowest detectable concentration of 10-10 M. As a real application, antibiotics sulfapyridine in milk is determined by using the proposed SERS protocol, and the limit of detection at 1 × 10-9 M could be reached. As a prospective, the ZnO/Ag@Au-based SERS method would be extended for food safety and biomedicine analysis.

The aim of the research was to investigate the anti-endotoxin and anti-inflammatory effects of Sinomenine, an agent commonly found in Chinese herbal medicines. Endotoxin (i.e., 1 mg lipopolysaccharide (LPS)/kg)) was administered via intraperitoneal (IP) injection to piglets in high-, middle-, and low-dose sinomenine groups. Piglets were then treated with 1, 5 or 10 mg/kg sinomenine, intramuscularly (i.m.), 3 hr after LPS. Vehicle was administered, as above, to drug control group piglets followed 3 hr later by 10 mg/kg sinomenine i.m.. LPS control group piglets were challenged with 1 mg/kg LPS IP, followed by vehicle i.m., and naive control piglets were treated with normal saline IP, followed by normal saline i.m., as above. Temperatures were measured, and blood samples were collected from the precaval veins of piglets at 12, 24, and 48 hr post-LPS or vehicle injection. Clinical signs were recorded, and index levels were analyzed via ELISA. Sinomenine was found to reduce the incidence and severity of LPS-induced toxicities, including body temperature elevation, cell adhesion, and systemic inflammation. These data suggest that sinomenine may be effective for regulating inflammatory responses and has the potential for use as an anti-endotoxin therapy.

Tilmicosin (TMS) is widely applied to treat porcine bacterial respiratory diseases in veterinary medicine. However, oral administration of TMS is greatly limited due to its physicochemical properties, such as poor water solubility, gastric acid sensitivity and bitterness. Therefore, nanostructured lipid carriers (NLCs) were developed as an oral delivery system for TMS by the high shear method combined with ultrasonic techniques in this study. The results showed that TMS-NLCs were approximately spherical with a hydrodynamic diameter of 283.03 nm and a zeta potential of -30.04 mV. TMS was almost entirely encapsulated in the NLCs by interacting with the lipid matrix, as characterized by differential scanning calorimetry and fourier transform infrared spectroscopy. Thus, TMS-NLCs had an excellent encapsulation efficiency and loading capacity with values of 93.46% and 9.23%, respectively. TMS-NLCs maintained good stability not only during storage at 4 ℃, 25 ℃ and 40 ℃ for 90 days but also in stimulated gastrointestinal (GI) fluids at 37 ℃ for 7 days. Therefore, TMS-NLCs displayed low and sustained release in vitro without an initial burst release in stimulated GI fluids. Furthermore, TMS-NLCs showed higher oral bioavailability in piglets compared to the API suspension. Subsequently, Caco-2 cell monolayers were utilized to analyze the mechanism of NLC-enhanced oral adsorption of TMS. The data revealed that NLCs not only increased cellular uptake of TMS but also inhibited the efflux of P-gp in Caco-2 cells. Additionally, TMS-NLCs mainly entered Caco-2 cells via the caveolae/lipid raft-mediated endocytosis pathway. Moreover, nanoparticles were transported across Caco-2 cell monolayers in the intact form to the basolateral side, as identified by transmission electron microscopy, indicating that TMS-NLCs escape lysosome degradation. Taken together, these results indicate that NLCs are a potential delivery carrier for improving the solubility, permeability and oral bioavailability of TMS.

A series of SBA-15 with different modifications have been successfully prepared and applied as adsorbents to remove polycyclic aromatic hydrocarbons (PAHs) from aqueous solutions. The morphology and structural properties of the chemically modified materials are all similar to those of pure SBA-15, and thus the difference of PAHs adsorption capacity can be directly attributed to the different functional groups, which is favorable to deeply explore the adsorption mechanism. Adsorption kinetics and isotherm experiments for naphthalene (Nap), anthracene (Ant), and pyrene (Pyr) were carried out, and the results reveal that the adsorption processes follow a pseudo-second-order rate equation and the equilibrium can be achieved within 120 min for Nap and Ant, whereas only 90 min for Pyr, indicating that the more hydrophobic molecules, the easier and faster adsorption can be obtained. All of the adsorption isotherms fit well with the Freundlich model, suggesting the unevenly distributed active sites on adsorbents. The phenyl-functionalized materials possess the highest adsorption capacity, implying that the π-π interaction is the most primary interaction and plays the predominant role in the studied PAHs adsorption, superior to the acidic and hydrophobic interaction. Our research sheds light on the design and synthesis of advanced and highly efficient adsorbents to remove PAHs from aqueous solutions.

The detection of urease activity in the oral cavity is considered to be an efficient way to prevent dental caries and also to screen for helicobacter pylori infection. Herein, a rapid surface enhanced Raman scattering (SERS) method is proposed to determine the activity of urease by using inositol hexaphosphate (IP6) stabilized silver nanoparticles (AgNPs@IP6) as an efficient SERS-active substrate. The determination was achieved by monitoring the SERS peak intensity of urea at 1003 cm−1. With urease increase, the response of urea at 1003 cm−1 decreases gradually, indicating the two has good correlation. A linear relationship between the absolute value of signal drop and urease concentration is observed in a range from 2.35 to 37.5 μg/mL. In addition, the rapid SERS method was used to evaluate the activity of urease in real sample of saliva without any pretreatment, exhibiting a promising potential for biomedical application.

Titanium dioxide, especially for black-colored TiO2, has aroused increasing attention in the field of solar energy storage and conversion in recent years. Nevertheless, it is reported the fabrication of black TiO2 normally requires a long reaction time and high temperatures, such complexity of method largely limits the fundamental understanding of black TiO2 and development of application for solar energy conversion. In this study, black TiO2 with tunable defects of Ti3+/Ov were successfully prepared from a facile method of NaN3 deflagration, which allows an ultrafast and productive formation of defective TiO2 at 450 o C. EPR spectra proved the substantial presence of Ti3+/Ov species in the obtained black products, which were produced during the ultrafast decomposition of NaN3, with oxygen atoms from TiO2 crystal seized by thermal and reductive Na clusters. Benefited from the introduction of defective Ti3+/Ov sites, the black sample DP-3 with modified energy band achieved an enlarged light absorption across the full solar spectrum. DP-3 demonstrated an impressive water evaporation rate of 1.624 kg m−2 h−1 and conversion efficiency of 85% under one-sun irradiation. To the best of our knowledge, the black TiO2 act as an effective solar-thermal system was firstly reported in our work. By applying the energy-releasing effect of NaN3, this study proposed a simple and fast way for the synthesis and modulation of TiO2 and providing a valuable application in photothermal evaporation.

AlCoCrFeNiSix (x = 0, 0.1, 0.2, 0.3, 0.4, 0.5) high-entropy alloy (HEA) coatings were deposited on the surface of AISI 304 stainless steel via laser cladding technology with different content of Si element. The evolution in microstructure, microhardness, and wear behavior of the coatings was investigated comprehensively to explore the effect of Si element. The results showed that the HEA coatings consisted of disordered Fe-Cr and ordered Al-Ni solid solution phases with a body-centered cubic (BCC) structure. Si element dissolved into the solid solutions, leading to lattice distortion. As Si content increased, the microstructure was refined, and a small quantity of Cr23C6 phase was precipitated along the grain boundaries. The microhardness of the coatings was linearly proportionate to Si content. The quantitative analysis revealed that the improvement of microhardness was dominated by the effect of dislocation strengthening, rather than solution strengthening and fine-grain strengthening. With the increase in Si content, the average friction coefficient and wear rate of the HEA coatings were all reduced remarkably, and the main wear mechanism evolved from adhesive wear, abrasive wear and delamination wear to oxidation wear. These phenomena were believed to be associated with the formation of the oxide film on the worn surface, which was identified as Fe2O3, Fe3O4, Cr2O3, SiO2, and SiO.

The CuO nanorods (NRs) are prepared with the help of inositol hexakisphosphate which serves as a binding agent and stabilizer. We have successfully fabricated Cu 2 O-decorated palladium networks (Cu 2 O/Pd Networks) by using such CuO NRs as reaction beds. Transmission electron microscopy images show that Cu 2 O/Pd network is composed of small and irregular fused nanoparticles with an average size of about 10 nm. Electrochemical results depict that the as-synthesized catalyst exhibits 2-fold higher activity for methanol oxidation than the commercially available 20% Pd/C catalyst and Pd black catalyst. Furthermore, CO-tolerance is also remarkably enhanced due to the presence of Cu 2 O. Such highly active, low-cost, and superiorly CO-tolerant catalysts of Cu 2 O/Pd Networks will open up a new avenue for direct methanol fuel cells.

Silver nanoparticle (AgNP)/poly(N-isopropylacrylamide) (PNIPAAm) composite solution was electrospun followed by crosslinking to fabricate AgNP/PNIPAAm composite nanofiber mats. Embedded AgNPs were found to align along the PNIPAAm nanofibers, which generate more hotspots upon laser-induced plasmonic heating. This kind of AgNP/PNIPAAm mats show enhanced surface-enhanced Raman scattering (SERS) effect upon continuous pulsed laser irradiation, showing a ‘laser heating sensitive’ SERS effect. Laser-induced plasmonic heating can also tune the temperature-responsive interaction between PNIPAAm and analytes and has been applied in the on-site ‘laser heating sensitive’ separation and SERS detection of analytes. The composite nanofiber mats also showed good reproducibility and stability. What is more, this ‘laser heating sensitivity’ has also been applied in the direct SERS detection of adenosine in urea solution without urea interference. Together with the advantages of ease of large-scale fabrication, stable and ‘laser heating sensitivity’, AgNP/PNIPAAm mats might find application in sensitive multicomponent biosensing. Copyright © 2016 John Wiley & Sons, Ltd.

Cubic-perovskite (SrTiO3) has a great potential to be utilized in a wide range of applications. However, currently very little is known about the shape and facet effects of SrTiO3 on their physicochemical properties. This is largely owing to the difficulties in controlling the morphology of facets during synthesis. Herein, we describe a facile route for the facet- and size-controlled fabrication of singlecrystalline SrTiO3 triangular prisms with highly exposed {101} side faces and {111} end faces. Theoretical and experimental studies of their photocatalytic performance have shown that triangular prisms exhibit superior photocatalytic activities than nanocubes with exposed (001) faces for the degradation of organic contaminants, which may be primarily attributed to the much higher surface energy of {101} facets (2.97 J/m2) and {111} facets (2.80 J/m2) than of that of {001} facets (0.98 J/m2).

We developed a highly sensitive surface-enhanced Raman scattering (SERS) technique for determining Fe3+ ions via synthesis of inositol hexaphosphate (IP6) capped silver nanoparticles (AgNPs). IP6 (1.98 nm thickness) coated on the surface of AgNPs not only provided a protection layer to stabilize silver substrate but also specifically anchoring sites of phosphates to capture Fe3+ ions from aqueous solution. Rhodamine 6G (R6G) was used as a Raman indicator in this case and the scattering intensity of R6G in Raman probe increased with adding Fe3+ ions. A possible mechanism is that IP6 bound with Fe3+ narrowed the gap of neighboring AgNPs to produce plenty of SERS “hot spots”. Due to the controllable aggregation of IP6@R6G–AgNPs by Fe3+, it presents a widely linear range of 11.2–39.2 ppm for analyzing the Fe3+ ions. This Raman-based method for detecting Fe3+ showed a high selectivity in the presence of other metal ions in same solution involving Mg2+, Cu2+, Ca2+, Pb2+, Co2+, Na+, Zn2+, K+, Li+, Mn2+ and Fe2+. Under optimal conditions, the limit of detection (LOD) for SERS testing Fe3+ could be down to 0.28 ppm. As a practical application, the Raman assay for the determination of Fe3+ in river water was carried out.