Search

Liver cancer is one of the most frequent causes of cancer-related deaths worldwide. The current study sought to screen, for the first time, a Ficus carica variety from the Shandong province of China against hepatocellular (HepG2) cells. Crude extracts of F. carica with various polarities were prepared and screened against HepG2 cells. The acetone extract of the leaf (FLA) exhibited significant antiproliferative effects against HepG2 cells (IC50 = 0.179 mg/mL) while producing the least toxicity on normal human umbilical vein endothelial cells (HUVECs). Biochemical evidence of apoptosis was confirmed by staining with DAPI and AO/EB. FLA also exhibited moderate anti-colonization potential against the population of HepG2 cells. It selectively arrested the cell cycle of HepG2 cells at the S phase and exerted anticancer activity by significantly increasing the reactive oxygen species (1.59 fold) inside the cells, which subsequently resulted in loss of the mitochondrial membrane potential as revealed by JC-1 probe assay. FLA downregulated the expression of tumor-promoter Transcription Factor (TP53), anti-apoptotic proteins (Bcl-2), and cell cycle regulatory kinases (CDK1, 5, 9) with respect to untreated cells for 24 h, 48 h, and 72 h. High-performance liquid chromatography (HPLC) of FLA revealed the presence of gallic acid and quercetin as major antiproliferative compounds along with trace amounts of rutin, luteolin, apigenin, benzoic acid, and β-sitosterol. Notably, our study showed FLA operating via novel mechanisms involving reactive oxygen species (ROS) generation and CDKs involvement in HepG2 cells. Thus, it suggests that FLA may be a potential source of new drugs in the treatment of liver cancer.

Inhibition of α-glucosidase is considered as an effective approach to treat type 2 diabetes. Therefore, it is of great significance to study the inhibition of this enzyme. In the present study, the inhibitory activity of oleanolic acid (OA) on α-glucosidase and their interaction mechanism were investigated. The inhibition kinetic analysis showed that OA reversibly inhibited α-glucosidase activity in a mixed-type manner with an IC50 value of 3.04 ± 0.05 µM, and the inhibition followed a multi-phase kinetic process with a first-order reaction. The change of enthalpy and entropy indicated that the binding of OA to glucosidase was mainly driven by hydrophobic interaction and hydrogen bonding, and the binding distance was estimated at 3.51 nm. Synchronous fluorescence, circular dichroism (CD) and Fourier transform infrared spectra (FT-IR) showed that the binding of OA to α-glucosidase induced rearrangement and conformational changes of the enzymes. The molecular docking illustrated that OA entered the active center of α-glucosidase and interacted with the amino acid residues Asp-352 and ultimately inhibiting the enzyme activity.

In the present study, antioxidant activities and functional properties of cowhide collagen antioxidant peptides (CCAPs) with different molecular weight (MW) were investigated. The optimum preparation conditions of CCAPs were hydrolysis time of 1.53 hr, temperature of 54.9 °C, pH 7.38, and neutral enzyme to trypsin ratio of 0.048 g: 0.016 g according to single factor test and response surface methodology (RSM). Three fractions (CCAP-I, CCAP-II, and CCAP-III) were obtained by ultrafiltration and lyophilization. Antioxidant activities revealed that CCAP-III had high reducing power activity (0.323 ± 0.035) and scavenging effect on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals (64.30 ± 5.99%), 2,2-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) radicals (75.25 ± 3.14%), and hydroxyl radicals (68.26 ± 6.74%) compared to the other fractions. In addition, LC-MS/MS analysis showed that Ala-Gly-Glu-Arg, Gly-Ile-Ala-Gly-Glu-Arg, Gly-Pro-Ala-Gly-Pro-Ala-Gly-Pro-Arg, Gly-Val-Val-Gly-Pro-Glu-Gly-Ala-Arg and Gly-Phe-Ser-Gly-Leu-Asp-Gly-Ala-Lys were the major peptides of CCAP-III. CCAP-III showed good hygroscopicity (HYG), water holding capacity (WHC), and oil holding capacity (OHC) when compared with CCAP-I and CCAP-II. However, CCAP-II has great emulsifying properties, and CCAP-I has excellent foaming properties. Therefore, CCAPs can be used as a promising source of functional peptides with antioxidant properties. PRACTICAL APPLICATION: This study demonstrated the peptides of cowhide collagen has superior antioxidant and functional properties. This study provided a scientific basis for the preparation of antioxidant peptides from cowhide collagen.

Usages of plastic casing have a number of drawbacks like generation of waste associated with the materials used to package foods and the source of natural casings is limited. So, the interest in the development of biodegradable collagen casing is increasing. For this reason, the present study aimed at developing a new type of collagen casing sprayed with Tea Polyphenols (TP), sodium alginate and sodium pyrophosphate. Box-Behnken Design (BBD) of Response Surface Methodology (RSM) was used to optimize concentrations of TP, sodium alginate and sodium pyrophosphate for the development of collagen casing. The optimization was done on the basis of responses viz. tensile force, tensile strength and elongation at break. The results showed that TP has a significant influence on tensile force and longitudinal tensile strength of collagen casing. Moreover, sodium alginate and sodium pyrophosphate had a significant effect on transverse elongation at break of collagen casing. The optimum level of different parameters resulting in collagen casing with maximum mechanical properties were obtained under conditions of 1.99% TP, 2.90% sodium alginate and 2.99% sodium pyrophosphate concentrations. Further verification test of the optimized conditions revealed a sufficient specific accuracy. The new type of collagen casing exhibited good mechanical properties, so these casings can be utilized for packaging in sausage industry.

α-Glucosidase is related to the increase in postprandial blood glucose in vivo.

Tea Polyphenols (TP) has received much attention for their excellent antioxidant and antibacterial activities. Some additives (such as sodium alginate and sodium pyrophosphate) have good hydrophobicity which have influence on the mechanical properties of food. The effect of TP on the antibacterial activity of collagen casing was investigated, the effect of addition of TP, sodium pyrophosphate and sodium alginate on mechanical properties including tensile force, tensile strength and elongation at break were also studied. Results from the single factor experiments demonstrated that TP showed strong antibacterial activities against Escherichia coli, Staphylococcus aureus and Salmonella according to the Minimum Inhibitory Concentration (MIC) and the inhibition zone method. Moreover, the mechanical properties of collagen casings were obviously influenced by the addition of TP and two food additives including sodium alginate and sodium pyrophosphate. This work would be useful for application of collagen casings with TP in food package to extend shelf-life of sausage during processing, transportation and storage.

Nanomaterial has diverse applications in electronics, catalysis, energy, materials chemistry and even biology due to the special properties endowed by their high specific surface ratio. However, nanoparticles can easily get agglomerated and lose their original properties, which has become one critical issue and limits its application in nanotechnology. Various surface modification methods were used to reduce its surface energy and prevent the agglomeration. While physical methods use surfactants to prevent the latter, chemical methods are more favorable, since the strong covalent bonds are more durable under wide range of conditions. Among these chemical modifications, chemical vapor deposition is extensively studied. Here we introduced nanomaterial’s characterization and reviewed different categories of chemical vapor deposition methods that have been used for nonmaterial’s surface modification. We showed that photo-induced chemical vapor deposition (PICVD) is an attractive strategy that could be carried out under normal temperature and pressure conditions; it might be the best potential candidate to be used widely in large-scale processes. Finally, we discussed the factors affecting functionalization process of PICVD and the research progress of its application in surface modification of nanoparticles.

Mitochondria and their electron transport pathway (ETP) might have a potential role in response to chilling stress. Notwithstanding, it is a novel area and the relative research is still in the early stages. In this study, we attempt to explore the explicit mechanisms of the 80% O2 + 20% CO2 treatment on alleviating chilling injury (CI) to white mushrooms based on the ETP and mitochondria, with natural air as the control. CI incidence, proportions of cytochrome pathway (CCP) and alternative pathway (AP), activities of key enzymes of CCP and AP, the relative gene expressions, mitochondrial structure and functions were investigated at 1 °C. The results reported that 80% O2 + 20% CO2 treatment prevented the occurrence of CI and retained the ATP yield. With regard to the ETP, the 80% O2 + 20% CO2 treatment restrained the decline in the proportion of CCP and boosted the proportion of AP through impacting the key enzymes and relative genes expressions. It also retarded mitochondria swelling and maintained higher levels of membrane fluidity and cytochrome c (Cyt c). Our results illustrated that 80% O2 + 20% CO2 dramatically alleviated the development of CI in white mushrooms, which could possibly be ascribed to the adjustment of ETP while retaining the structure and functions of the mitochondrion and the switching of its two conformations.

In this study, the effect of Walnut Leaf Polysaccharides (WLP) on human liver tumor HepG2 cells was investigated. The results showed that WLP had dose-dependent and time-dependent inhibitory effects on HepG2 cell viability. Typical apoptosis characteristics were observed in WLP-treated HepG2 cells through 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazolyl-carbocyanine iodide (DAPI) staining and Acridine Orange (AO)/Ethidium Bromide (EB) dual staining. Meanwhile, significant decrease in Mitochondrial Membrane Potential (MMP) and increase in intracellular Reactive Oxygen Species (ROS) levels of WLP-induced HepG2 cells were detected by 5,5',6,6'-Tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine iodide (JC-1) and 2',7'-Dichlorodihydrofluorescein Diacetate (DCFH-DA) fluorescent probes, respectively. Moreover, cell viability, MMP and ROS level of HepG2 cells were observed after intervention with antioxidant NAC. Thus, we speculated that WLP may induce apoptosis of HepG2 cells by decreasing MMP and increasing intracellular ROS levels. The results suggest that WLP could be developed as a promising natural anticancer active substance in the pharmaceutical and functional food industries.

Tyrosinase is the rate-limiting enzyme controlling the production of melanin, and tyrosinase inhibitors can regulate the overproduction of melanin by inhibiting tyrosinase activity, which is an effective method to treat pigmentation disorders. In this study, kinetic analysis, multispectroscopic methods and molecular simulation were used to investigate the inhibitory activity and mechanism of trilobatin on tyrosinase. The kinetic analysis showed that trilobatin had significant inhibitory activity on tyrosinase in a reversible and mixed-type manner with IC50 values of (2.24 ± 0.35) × 10-5 mol L-1. The intrinsic fluorescence of tyrosinase was quenched by trilobatin through a static quenching mechanism. Different spectroscopic measurements demonstrated that trilobatin could change the microenvironments and conformation of tyrosinase and molecular docking determined the binding site of quercetin on tyrosinase.

The new era puts forward higher requirements on the quality of hospital management personnel, so it is significant to improve their health management research capabilities and encourage them to solve practical difficulties through scientific research as well as make innovations to their management thinking. In this article, a questionnaire survey of 100 hospital management personnel was carried out in a tertiary hospital in Guangzhou, China, to identify their health management research capabilities and learning needs for related knowledge. The results showed that most of the interviewees were young and middle-aged women with relatively high academic qualifications, mainly in medical and management majors. Their scientific research knowledge base and learning needs are on the average, and their scientific research method foundation is relatively ideal. There are significant differences in scientific research knowledge base, scientific research training needs, and scientific research methods among those with different ages and educational levels (p

Despite developments in surgery and chemotherapy, effective treatment of breast cancer is still an urgent problem owing to recurrence and metastasis. By combining the advantages of curcumin (Cur), zeolitic imidazolate framework-8 nanoparticles (ZIF-8), and hyaluronic acid (HA) in breast cancer therapy, Cur-loaded and HA-coated ZIF-8 (Cur@ZIF-8@HA) were synthesized using a method based on the pH-dependent solubility of Cur and the electrostatic interactions between zinc ions and carboxyl groups of HA. Cur@ZIF-8 were also prepared as a control group. Comprehensive comparisons of the physicochemical properties and anticancer activities of Cur@ZIF-8@HA and Cur@ZIF-8 were conducted. The results indicated that the degradation of Cur during the synthesis of Cur@ZIF-8 was negligible. The obtained Cur@ZIF-8 and Cur@ZIF-8@HA were truncated cubes with hydrodynamic diameters of 174 and 217 nm, respectively. Cur@ZIF-8@HA possessed better stability during storage in different media, a slower drug release rate under neutral and acidic conditions, and a greater inhibitory effect on breast cancer than Cur@ZIF-8. For 4T1 cells, treatment using Cur@ZIF-8@HA induced more cellular uptake and higher cytotoxicity, accompanied by higher lactate dehydrogenase release, cell cycle arrest in G2/M and S phases, production of reactive oxygen species, and apoptosis. In 4T1 tumor-bearing mice models, Cur@ZIF-8@HA showed a stronger inhibitory effect on tumor growth and pulmonary metastasis. Therefore, Cur@ZIF-8@HA might hold great potential as an agent for the effective therapy of breast cancer.

Human liver cancer has emerged as a serious health concern in the world, associated with poorly available therapies. The Berberis genus contains vital medicinal plants with miraculous healing properties and a wide range of bioactivities. In this study, different crude extracts of B. lycium Royle were prepared and screened against Human Hepatocarcinoma (HepG2) cell lines. The water/ethanolic extract of B. lycium Royle (BLE) exhibited significant antiproliferative activity against the HepG2 cancer cell line with an IC50 value of 47 μg/mL. The extract decreased the clonogenic potential of HepG2 cells in a dose-dependent manner. It induced apoptotic cell death in HepG2 cells that were confirmed by cytometric analysis and microscopic examination of cellular morphology through DAPI-stained cells. Biochemical evidence of apoptosis came from elevating the intracellular ROS level that was accompanied by the loss of mitochondrial membrane potential. The mechanism of apoptosis was further confirmed by gene expression analysis using RT-qPCR that revealed the decline in Bcl-2 independent of p53 mRNA and a rise in CDK1 while downregulating CDK5, CDK9, and CDK10 mRNA levels at 48 h of BLE treatment. The most active fraction was subjected to HPLC which indicated the presence of berberine (48 μg/mL) and benzoic acid (15.8 μg/mL) as major compounds in BLE and a trace amount of luteolin, rutin, and gallic acid. Our study highlighted the importance of the most active BLE extract as an excellent source of nutraceuticals against Human Hepatocarcinoma that can serve as an herbal natural cure against liver cancer.

Ochratoxins are highly toxic contaminants and considerable threat to the health of humans and animals. Ochratoxins, mainly include ochratoxin A (OTA), ochratoxin B (OTB) and ochratoxin C (OTC), always exist in the food raw materials with the form of the mixture and they can convert to each other easily under special environment. The co-occurrence of three ochratoxins and conversion between different types of major ochratoxins make the specific detection for a separate kind of ochratoxin can not fully meet the rapid analysis demand of ochratoxins. Thus, the simultaneous detection for three major ochratoxins is urgent and indispensable. Here, a monoclonal antibody (mAb) which could simultaneously recognize OTA, OTB and OTC was screened out and then based on the mAb, an immunochromatographic assay (ICA) for rapid detection of the three major ochratoxins was first developed. After optimization, the visible limits of detection (vLODs) were 0.05, 0.025, 0.1 ng/mL and the cut-off concentrations were 0.5, 0.25, 0.5 ng/mL for OTA, OTB and OTC, respectively. Finally, the assay was evaluated using ochratoxins spiked maize samples, and results showed that the developed ICA could provide a practical method for the detection of three major ochratoxins on-site.

A facile electrostatic deposition method was proposed to encapsulate quercetin within chitosan/lecithin polymeric nanocapsules, with the aim to protect quercetin against degradation and enhance its biocompatibility. Quercetin loaded polymeric nanocapsules (Q-NPs) were characterized in terms of size, morphology, encapsulation efficiency, storage stability, anti-oxidant and anti-proliferative activities. The obtained homogeneous and spherical Q-NPs have small particle size and high encapsulation efficiency (71.14%). The storage stability and antioxidant activity was improved compared with native quercetin. MTT assay and trypan blue exclusion assay showed the inhibitory effect of Q-NPs on HepG2 cells were comparable with that of free quercetin. This novel nanocapsule may provide a new system for the protection and delivery of a range of hydrophobic chemicals in vivo and food products.

In this work, the double-edged effect of curcumin (Cur) on Maillard reaction (MR) in model milk pasteurization process was demonstrated for the first time, where Cur inhibits MR at low concentrations ( 5 μg/mL). A nanocapsule strategy was introduced to resolve the disadvantages of Cur on MR at high temperature. In vitro experiments confirmed that curcumin @ polyvinylpyrrolidone nanocapsules (Cur@PVP NCs) synthesized by a one-pot method can control the continuous and slow release of Cur and exert inhibitory effect on MR by competing with lactose for casein, trapping the reactive dicarbonyl compounds and scavenging ROS, which might provide a new strategy for the application of functional food ingredients in the control of MR during food heat processing, including milk pasteurization.

In this paper, the optimum extraction conditions of total flavonoids extracted from walnut leaves subjected to Ultrasonic Assisted Extraction (UAE) were optimized by Response Surface Methodology (RSM). The mathematical model showed the high coefficient of measurement (R2 = 0.9938) which indicated that this model could be used to guide the response surface methodology. The optimum extraction parameters for extracting flavonoids from walnut leaves determined in this study were extraction temperature 47.73°C, extraction time 30.79 min, ethanol concentration 72.89% (v/v). Under the optimal extraction conditions, the flavonoids yield was about 3.5315%. Statistical analysis of the results showed that extraction temperature, extraction time and ethanol concentration significantly affected the extraction yield of total flavonoids. In addition, the antibacterial activity assays of the flavonoids were carried out and it was demonstrated that the total flavonoids extracted at the optimum conditions had pronounced antibacterial effects against the four bacterial species. Therefore, this study suggested that walnut leaves are promising resources with antibacterial properties for the development of phytomedicines.

Currently, melatonin (N-acetyl-5-methoxytrytamine) is recognized as a potential scavenger of free radicals. In this study, the effect of exogenous melatonin at various concentrations (0.05, 0.1, and 0.2 mM) on the texture, sensory qualities, and electron leakage in white mushrooms was evaluated at 3 ± 1 °C. It was observed that mushrooms treated with 0.1 mM melatonin were of good quality and their electron leakage was dramatically dampened. The results showed that 0.1 mM melatonin retained a higher adenosine triphosphate level and also prevented the release of cytochrome c into the cytoplasm. More significantly, it prominently inhibited electron leakage by increasing the activities of complexes I and III by the upregulation of AbNdufB9 and AbRIP1. It also regulated respiratory states in mushrooms; delayed the decline of respiratory state 3; enhanced respiratory state 4; boosted the oxidative phosphorylation and efficiency of mitochondria; and ultimately retarded the senescence of the white mushrooms.

In recent years, China has been actively promoting the Belt and Road Initiative. In the context of the gradual opening of the medical market, it is urgent to improve the health management knowledge and scientific research capabilities of the hospital administrators, further enhance the hospital management level, so that the hospitals can obtain a greater edge in the international medical competition. Using overseas intelligence to promote the internationalization of education is one of the important means. The Affiliated Cancer Hospital and Institute of Guangzhou Medical University has invited Portuguese management professors to establish an academic and educational cooperation relationship, and invited them to offer training for hospital administrators. This article uses questionnaires to survey the trainees participating in this training and evaluates the teaching quality of overseas teachers. The results showthat the interviewed students generally present high affirmation to the training effects of the training courses and the teaching quality of overseas distinguished teachers.

Nanoceria (cerium oxide nanoparticles) exhibits excellent catalytic activity towards chromogenic substrate 3,3,5,5-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H2O2), which has been reported. However, the understanding of the interaction between H2O2 and nanoceria is far from comprehensive. Herein, we further studied the interaction between H2O2 and dextran-coated nanoceria and found that H2O2 plays a dual role in nanoceria's oxidase activity both as an inhibitor and a promoter, depending on its concentration. At millimolar levels, H2O2 can promote nanoceria's oxidase activity; however, micromolar concentrations of H2O2 can inhibit its catalytic activity. In addition, this inhibiting effect is linearly dependent on the concentration of H2O2. Based on these findings, a simple, rapid and highly sensitive colorimetric method was established for the determination of H2O2 with a limit of detection (LOD) of 2.5 μM (3σ/slope) and a linear range from 4−40 μM. When coupled with glucose oxidase, glucose can be detected down to 2 μM in the linear range of 4−40 μM. Furthermore, this method was successfully applied in the determination of glucose in mouse serum samples. With the new understanding of the interaction between H2O2 and nanoceria, applications of nanoceria-based sensors in engineering, biotechnology and environmental chemistry can be further exploited.

A facile pH-assisted method for synthesizing curcumin-functionalized selenium nanoparticles (SeNPs@Cur) with enhanced cancer chemopreventive activity is proposed in the present work. It is intriguing to observe that by controlling the pH value of the synthetic reaction system, water-insoluble Cur is successfully decorated on the surfaces of SeNPs@Cur through physical adsorption and the possible formation of Se–O bonds. Moreover, the as-prepared nanocomposites possess high drug conjugation efficiency (5.5%), good chemical stability and more uniform sizes and morphologies in comparison with bare SeNPs. Meanwhile, enhanced chemopreventive activity of SeNPs@Cur is demonstrated through the improvements of their free radical scavenging activities and the increases of their cytotoxicities against cancer cells. Cur surface decoration also increases cellular uptake of elemental Se and apoptosis in HepG2 cells. Studies on underlying mechanisms suggest that SeNPs@Cur-induced apoptosis is dependent on the activation of caspases and the overproduction of intracellular ROS. In conclusion, data herein indicate that the strategy to assemble antioxidant ligands on the surface of SeNPs is a potential way to design novel chemopreventive agents with better safety, tolerability and efficacy profiles.

Bisphenol S, the most ideal alternative of bisphenol A, has been proved to be toxic towards human. However, up to now, there is no rapid detection method established to cater to the on-site determination of bisphenol S. Herein, we pioneered an electrochemically co-reduced graphene oxide-C 60 nanoassembly based electrochemical platform to cover this shortage. This nanoassembly synthesized by simple grinding and electrochemical reduction shows excellent electrocatalytic activity towards bisphenol S, and the novel electroanalytical platform allows a sensitive determination of bisphenol S in the range of 1–100 μM with a detection limit of 0.5 μM. Moreover, this sensor was utilized to determine bisphenol S in milk, emerging good anti-interference ability and acceptable recovery.

Herein, the structure of two DNA strands which are complementary except fourteen T-T and C-C mismatches was programmed for the design of the combinatorial logic operation by utilizing the different protective capacities of single chain DNA, part-hybridized DNA and completed-hybridized DNA on unmodified gold nanoparticles. In the presence of either Hg(2+) or Ag(+), the T-Hg(2+)-T or C-Ag(+)-C coordination chemistry could lead to the formation of part-hybridized DNA which keeps gold nanoparticles from clumping after the addition of 40 μL 0.2M NaClO4 solution, but the protection would be screened by 120 μL 0.2M NaClO4 solution. While the coexistence of Hg(2+), Ag(+) caused the formation of completed-hybridized DNA and the protection for gold nanoparticles lost in either 40 μL or 120 μL NaClO4 solutions. Benefiting from sharing of the same inputs of Hg(2+) and Ag(+), OR and AND logic gates were easily integrated into a simple colorimetric combinatorial logic operation in one system, which make it possible to execute logic gates in parallel to mimic arithmetic calculations on a binary digit. Furthermore, two other logic gates including INHIBIT1 and INHIBIT2 were realized to integrated with OR logic gate both for simultaneous qualitative discrimination and quantitative determination of Hg(2+) and Ag(+). Results indicate that the developed logic system based on the different protective capacities of DNA structure on gold nanoparticles provides a new pathway for the design of the combinatorial logic operation in one system and presents a useful strategy for development of advanced sensors, which may have potential applications in multiplex chemical analysis and molecular-scale computer design.

A prerequisite for exploiting most proposed applications for MoS2 is the availability of water-dispersible functionalized MoS2 nanosheets in large quantities. Here we report one-step synthesis and surface functionalization of MoS2 nanosheets by a facile ionic liquid assisted grinding method in the presence of chitosan. The selected ionic liquid with suitable surface energy could efficiently overcome the van der Waals force between the MoS2 layers. Meanwhile, chitosan molecules bind to the plane of MoS2 sheets non-covalently, which prevents the reassembling of exfoliated MoS2 sheets and facilitates the exfoliation progress. The obtained chitosan functionalized MoS2 nanosheets possess favorable stability and biocompatibility, which renders them as promising and biocompatible near-infrared agents for photothermal ablation of cancer. This contribution provides a facile way for the green, one-step and large-scale synthesis of advanced functional MoS2 materials.

This paper described a facile green electrochemical approach to synthesize graphene-AuNRs nanocomposite (GN-AuNRs) onto glassy carbon electrode (GCE) for electrocatalytic analysis of methyl parathion (MP). This electrochemical synthesis of GN-AuNRs hybrid is environmentally friendly for not involving the chemical reduction of graphene oxide (GO) and facile for just on the basis of electrostatic interaction between GO and AuNRs, as well as electrochemical reduction of GO-AuNRs to GN-AuNRs. Combined the high conductivity, large surface area, good adsorption capacity towards aromatic rings and high catalytic ability of graphene with the excellent electronic properties and adsorption capacity of AuNRs, the high sensitive methyl parathion sensor was fabricated with the GN-AuNRs nanocomposite. The limit of detection (LOD) of the proposed sensor was calculated to be 0.82 ng/mL, which was lower than many previously reported enzyme or nonenzyme-based sensors. In the meantime, the linear detection range of this sensor was from 10 to 500 ng/mL and 750 to 4000 ng/mL, which was also wider than many other enzyme or enzymeless sensors. Furthermore, the facile and green electrochemical reduction strategy provided here could also be used to construct more GN-based hybrids. And the GN-based hybrid might be a new and highly efficient SPE factor, which opens new opportunities for green, facile and sensitive analysis of nitroaromatic OPs such as MP.

Oxygen evolution reaction (OER) plays a key role in various energy conversion and storage technologies, such as water electrolysis, regenerative fuel cells, and rechargeable metal–air batteries. However, the slow kinetics of OER limit the performance and commercialization of such devices. Herein, we report on NiFe LDH@Au hybrid nanoarrays on Ni foam for much enhanced OER. By hybridization of electronegative Au and NiFe LDH with intrinsic remarkable OER catalytic activity, this modular electrode could drive an overall ultrahigh-performance and robust OER in base with the demand of overpotentials of only 221, 235, and 270 mV to afford 50, 100, and 500 mA cm–2, respectively. Also, it exhibits superior catalytic activity and durability toward OER in 30 wt % KOH.

We describe a method for the visual and colorimetric determination of total nereistoxin-related insecticide residues. It is based on the nereistoxin-induced aggregation of gold nanoparticles (AuNPs). The nereistoxin-related insecticides are first converted to nereistoxins in a pretreatment step that involves liquid–liquid extraction and hydrolysis for sample clean-up. Next, the interaction between nereistoxins and AuNPs provides a possibility to visually semi-quantify or accurately quantify nereistoxins because it is associated with a color change from red to blue. The interaction between nereistoxins and AuNPs is caused by the electrostatic interactions and the strong Au–S covalent bonds. The photometric assay is performed by measuring the ratio of absorbances at 660 and 519 nm, respectively. It has a detection range from 50 to 250 μg kg−1 and a detection limit of 40 μg kg−1 to for the total quantity of nereistoxin-related insecticides. The visually detectable color change to blue occurs in the 50 to 100 μg kg−1 concentration range, and this enables a fast visual test on whether or not the concentration of total nereistoxin-related insecticides exceeds the tolerated level of 100 μg kg−1. The method was applied to the analysis of nereistoxin-related insecticides in agricultural products.

This work demonstrated that graphene oxide (GO) could not only be exploited as a nanovector to efficiently transfer π-conjugated polyene biomolecules from the organic phase to the aqueous phase, but also could enhance light-thermal stability and bioactivity of the transferred π-conjugated polyene biomolecules.

Biologically, MoS2-based nanostructures have been intensely applied for the photothermal therapy of cancer, but rarely for antibacterial uses. In this contribution, a multifunctional chitosan (CS) functionalized magnetic MoS2 (abbreviated to CFM) was constructed to nonspecifically combat bacterial infection by integrating bacterial conjugation and enrichment, and NIR-triggered photothermal sterilization. Owing to the abundant introduced amino groups, the CFM complex offers a significantly enhanced conjugation efficiency without obvious specificity towards both Gram-positive and -negative bacteria compared to amino-free magnetic MoS2. The magnetic properties of CFM obtained from iron oxide facilitate the enrichment of a CFM–bacteria conjugate, improving the photothermal efficiency of CFM as a photothermal antibacterial agent. Specifically, after being trapped together with bacteria cells, CFM shows an enhanced in vitro photothermal sterilization ability. In vivo S. aureus-induced abscess treatment studies show faster healing when CFM is used as subcutaneous nano-localized heating sources with the assistance of an external magnet to concentrate the CFM–bacteria conjugate. This work establishes an innovative solution and a novel antimicrobial agent for combating bacterial infections without the use of antibiotics, which may open a new area of application and research for MoS2-based nanostructures.

As one of most common synthetic phenolic antioxidants, tertiary butylhydroquinone (TBHQ) has received increasing attention due to the potential risk for liver damage and carcinogenesis. Herein, a simple and rapid fluorescent switchable methodology was developed for highly selective and sensitive determination of TBHQ by utilizing the competitive interaction between the photoinduced electron transfer (PET) effect of carbon dots (CDs)/Fe(III) ions and the complexation reaction of TBHQ/Fe(III) ions. This novel fluorescent switchable sensing platform allows determining TBHQ in a wider range from 0.5 to 80 μg mL(-1) with a low detection limit of 0.01 μg mL(-1). Furthermore, high specificity and good accuracy with recoveries ranging from 94.29 to 105.82% in spiked edible oil samples are obtained with the present method, confirming its applicability for the trace detection of TBHQ in a complex food matrix. Thus, the present method provides a novel and effective fluorescent approach for rapid and specific screening of TBHQ in common products, which is beneficial for monitoring and reducing the risk of TBHQ overuse during food storage.

Developing low-cost, efficient, and bifunctional electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is an appealing yet challenging task. Herein, for the first time, a NiS microsphere film was grown in situ on Ni foam (NiS/Ni foam) via a sulfurization reaction as an efficient bifunctional electrocatalyst for overall water splitting with superior activity and good durability. This NiS/Ni foam electrode delivers 20 mA cm(-2) at an overpotential of 158 mV for the HER and 50 mA cm(-2) at an overpotential of 335 mV for the OER in 1.0 M KOH. This bifunctional electrode also enables a high-efficiency alkaline water electrolyzer with 10 mA cm(-2) at a cell voltage of only 1.64 V, which could be promising in water splitting devices for large-scale hydrogen production.

Selenium nanoparticles (Se NPs) possess well-known excellent biological activities and low toxicity, and have been employed for numerous applications except as inhibitors to protein glycation. Herein, the present study is carried out to investigate the inhibitory effect of Se NPs on protein glycation in a bovine serum albumin (BSA)/glucose system. By measuring the amount of glucose covalently bound onto BSA, the formation of fructosamine and fluorescent products, it is found that Se NPs can hinder the development of protein glycation in a dose-dependent but time-independent manner under the selected reaction conditions (55 °C, 40 h). And after comparing the increase of inhibitory rate in different stages, it is observed that Se NPs show the greatest inhibitory effect in the early stage, then in the advanced stage, but no effect in the intermediate stage. Fourier transform infrared spectroscopy characterization of Se NPs collected after glycation and determination of ·OH influence and glyoxal formation show that the mechanism for the inhibitory efficacy of Se NPs is related to their strong competitive activity against available amino groups in proteins, their great scavenging activity on reactive oxygen species and their inhibitory effect on α-dicarbonyl compounds' formation. In addition, it is proved that Se NPs protect proteins from structural modifications in the system and they do not exhibit significant cytotoxicity towards BV-2 and BRL-3A cells at low concentrations (10 and 50 μg mL(-1)). Consequently, Se NPs may be suitable for further in vivo studies as novel anti-glycation agents.

Existence of endotoxin in food and injection products indicates bacterial contaminations and therefore poses threat to human health. Herein, a simple and rapid colorimetric method for the effective detection of endotoxin in food and injections based on counterion-mediated gold nanorods aggregation is first proposed. By taking advantage of the color change of unmodified gold nanorods resulted from endotoxin mediated gold nanorods aggregation, endotoxin could be detected in the concentration range of 0.01–0.6 μM. Further, we studied the performance of gold nanorods with different aspect ratios (2.7 and 3.3) in determination of endotoxin and found that gold nanorods with higher aspect ratio (AR) showed superiority in the sensing sensitivity of endotoxin. A good specificity for endotoxin, a detection limit of 0.0084 μM and recoveries ranging from 84% to 109% in spiked food and injection samples are obtained with the colorimetric method. Results demonstrate that the present method provides a novel and effective approach for on-site screening of endotoxin in common products, which is beneficial for monitoring and reducing the risk of bacterial contaminations in food and injections production.