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Medicine food homologous (MFH) plants provide therapeutic and health care effects through diet. Thus, a risk assessment system for hazardous ingredient residues is urgently required to ensure their safe use. In this study, the pesticide contamination of six root and rhizome Chinese herbs, Ginseng Radix et Rhizoma, Panacis Quinquefolii Radix, Pseudostellariae Radix, Salviae Miltiorrhizae Radix et Rhizoma, Codonopsis Radix, and Glehniae Radix, and the risks associated with their intake were investigated. A total of 420 MFH plant samples collected from 22 provinces in China were tested, and 61 pesticides were detected in 413 samples. Multiple pesticide residues were detected in each MFH sample, with contents ranging from 0.0002 to 3.010 mg/kg dry weight. Carbendazim (≥47.14%) and propham (≥40%) were the most frequently detected pesticides. Risk assessment determined by hazard quotients indicated that the risks were acceptable, with no short‐ or long‐term adverse health effects. However, considering the high incidence of residues and the detection of unregistered or even prohibited pesticides, strict supervision of soil quality and pesticide application (particularly cadusafos) in MFH plant cultivation are recommended to aid in monitoring MFH plant quality and ensuring diet and drug safety. Practical Application: Ensure the diet and drug safety of Chinese herbs. [ABSTRACT FROM AUTHOR]

Mesoporous carbon hollow spheres coated with MoS2 (C@MoS2) were synthesized to obtain a material with large specific surface area, fast electron transfer efficiency and good water dispersibility. The composite material was applied as a matrix for the analysis of small molecules by surface-assisted laser desorption/ionization time-of-flight mass spectrometry (SALDI-TOF MS). The use of a core-shell C@MoS2 matrix strongly reduces matrix background interferences and increases signal intensity in the analysis of sulfonamides antibiotics (SAs), cationic dyes, emodin, as well as estrogen and amino acids. The composite material was applied to the SALDI-TOF MS analysis of selected molecules in (spiked) real samples. The ionization mechanism of the core-shell C@MoS2 as a matrix is discussed. The method exhibits low fragmentation interference, excellent ionization efficiency, high reproducibility and satisfactory salt tolerance. [ABSTRACT FROM AUTHOR]

A 2D Z-scheme BiVO4/g-C3N4 photocatalyst was successfully synthesized by a two-step hydrothermal/calcination method for overall water splitting. Morphology design to restrain the growth of BiVO4 nanoplates with thickness around 20 nm was achieved by adjusting the pH value and introducing graphene sheets. Then, the BiVO4/g-C3N4 (BVO-CN) hybrid photocatalysts were fabricated with different mass ratios of two components. The structures and optical properties of the BVO-CN photocatalysts were characterized by transmission electron microscope, scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, and photoluminescence spectroscopy. In application, the BVO-CN photocatalysts exhibited the catalytic overall water splitting activity up to 15.6 μmol h−1 for H2 production and 7.3 μmol h−1 for O2 evolution under visible light irradiation. A possible Z-scheme mechanism is proposed for the enhanced photocatalytic activity and was further confirmed by electron spin resonance spectroscopy. This study demonstrated enhanced overall water splitting photocatalytic performance of BiVO4/g-C3N4 photocatalyst by constructing a 2D nanoplates morphology and shed light on the morphology design of Z-scheme semiconductor materials. [ABSTRACT FROM AUTHOR]

Cancer is the leading cause of death worldwide, and metastasis is the main attribute to cancer death. CXCR4 and its natural ligand CXCL12 have been known to play a critical role in tumorigenesis, angiogenesis and metastasis. Therefore, designing a new CXCR4 antagonist to prevent tumor metastasis will be of great significance. Herein, a novel chemically synthesized peptide (E5) that has an ability to target CXCR4/CXCL12 axis was loaded in micelle glycol-phosphatidylethanolamine (PEG-PE) block copolymer to form micelle-encapsulated E5 (M-E5). We demonstrated that M-E5 exhibited higher affinity for CXCR4-overexpressing MCF-7 and HepG2 tumor cells as compared to free E5, and efficiently inhibited the tumor cells migration. Mechanistic studies implied that PEG-PE micelle can encapsulate E5 and improve E5 targeting efficiency for CXCR4 by accumulating E5 on the tumor cell membrane. Furthermore, through encapsulation of chemotherapeutic drug doxorubicin (Dox) in PEG-PE micelle, we proved that PEG-PE micelle could serve as a co-carrier for both E5 and Dox (M-E5-Dox). M-E5 enhanced the efficiency of Dox by down-regulating the phosphorylation level of Akt, Erk and p38/MAPK proteins. In conclusion, PEG-PE micelle demonstrated a promising delivery system for E5, and M-E5 is expected to be a potential therapeutic agent that will help to improve the clinical benefits in current therapies used for solid tumors. [ABSTRACT FROM AUTHOR]

• A g-C 3 N 4 -based sorbent exfoliated by ZIF-67 in-situ is fabricated for dSPE of PFCs. • The hybrid materials possess thinner layers of g-C 3 N 4 and small crystal of ZIF-67. • The method was applied in analysis of PFCs in water samples with low MDLs. Monitoring the levels of perfluorinated compounds (PFCs) in the environment is of vital importance, owing to their sustained environmental presence, extensive distribution, and associated health risks. The development of cost-effective and efficient sorbents for the establishment of sensitive analytical methods is critical for achieving trace-level detection. In this study, a graphitic carbon nitride (g-C 3 N 4)-based sorbent is synthesized by a facile sonication-assisted method exfoliated by zeolitic imidazolate framework-67 (ZIF-67) in situ. The novel ZIF-67/g-C 3 N 4 composites were systematically characterized by transmission electron microscopy, scanning electron microscopy, atomic force microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, and N 2 adsorption–desorption analysis, exhibiting good dispersity and a large surface area. Moreover, molecular dynamics simulations indicated that g-C 3 N 4 structures can be effectively exfoliated by the introduced ZIF-67 molecules. The hybrid material was successfully utilized as a dispersive solid-phase extraction sorbent, and the extraction factors were systematically optimized by response surface methodology. Under optimal conditions, the synthesized sorbent exhibited desirable linear correlations (R 2 > 0.99), a low detection limit (0.3–2 ng L−1), and good repeatability (relative standard deviation <15%, n = 6). The developed method was applied for the analysis of natural and spiked water samples. The study demonstrated that the ZIF-67/g-C 3 N 4 composites are promising materials for pollutant adsorption from drinking water samples. [ABSTRACT FROM AUTHOR]

• An efficient MALDI-MS strategy to differentiate Fritillaria species with an instant sample preparation. • Integrated MS data analysis procedure for metabolic analysis. • Chemical taxonomy for closely related Fritillaria species, which is consistent with genetic taxonomy. The bulbs of Fritillaria have been used for centuries as food and medicinal products in many Asian countries. Different Fritillaria species have distinct pharmacological effects despite of their similar appearances. Effective differentiation of Fritillaria species can avoid adulteration and is crucial to its clinical uses. In this paper, a hybrid method of matrix assisted laser desorption/ionization mass spectrometry and multivariate statistical analysis was developed for the rapid and reliable differentiation of Fritillaria species for the first time. Significantly different patterns for five Fritillaria species were obtained by MALDI-MS after instant sample extractions. Different groups of Fritillaria were confidently differentiated via an orthogonal partial least square model. In addition, a metabolomic taxonomy of five Fritillaria species was obtained based on MALDI-MS data. [ABSTRACT FROM AUTHOR]

Rationale: A thorough understanding of the content and distribution of active ingredients in pharmaceuticals is essential for drug efficacy and safety. Technological advancements in mass spectrometry imaging present an opportunity for methodological innovation by providing qualification and quantification analysis, as well as spatial information, in the same assay, which has great potential for applications in the rapid analysis and quality control of drugs. Methods: Matrix‐assisted laser desorption/ionization mass spectrometry imaging (MALDI‐MSI) was employed to directly analyze oxytetracycline tablets in order to map the distribution of the active constituent within the whole tablet. Quantitative analysis was capable of differentiating tablets containing various doses of the active pharmaceutical ingredient. Results: To establish the methodology, detailed factors that influence matrix spraying and spatial resolution during sample preparation and the data acquisition process were optimized systematically. Quantitative analysis could differentiate the tablets containing various doses of the active compound. The proposed method was successfully applied to analyze real commercial tablets. Conclusions: The developed method could successfully achieve the spatial location of oxytetracycline in actual tablet samples. These results could contribute to pharmaceutical tracing technology, especially the formulation process of tablets, which is helpful for monitoring the quality of pharmaceutical products and guaranteeing drug security. [ABSTRACT FROM AUTHOR]

The reduction of selenite [Se(Ⅳ)] by microorganisms is a green and efficient detoxification strategy. We found that Se(Ⅳ) inhibited exopolysaccharide and protein secretion by Lactiplantibacillus plantarum BSe and compromised cell integrity. In this study, L. plantarum BSe reduced Se(Ⅳ) by increasing related enzyme activity and electron transfer. Genomic analysis demonstrated that L. plantarum BSe should be able to reduce Se(Ⅳ). Further transcriptome analysis showed that L. plantarum BSe enhanced its tolerance to Se(Ⅳ) by upregulating the expression of surface proteins and transporters, thus reducing the extracellular Se(Ⅳ) concentration through related enzymatic reactions and siderophore-mediated pathways. Lactiplantibacillus plantarum BSe was able to regulate the expression of related genes involved in quorum sensing and a two-component system and then select appropriate strategies for Se(Ⅳ) transformation in response to varying environmental Se(Ⅳ) concentrations. In addition, azo reductase was linked to the reduction of Se(Ⅳ) for the first time. The present study established a multipath model for the reduction of Se(Ⅳ) by L. plantarum , providing new insights into the biological reduction of Se(Ⅳ) and the biogeochemical cycle of selenium. [Display omitted] • Se(Ⅳ) compromised cell integrity of L. plantarum BSe and inhibited EPS secretion. • BSe reduces Se(Ⅳ) by improving enzyme activity and electron transfer. • BSe upregulated surface proteins and transporters to resist the Se(Ⅳ) stress. • Azo reductase was found to be related to the reduction of Se(Ⅳ) for the first time. [ABSTRACT FROM AUTHOR]

The design and synthesis of effective photocatalysts for photodegradation of persistent organic pollutants is of significant importance. Novel CuFe2O4 microspheres were successfully synthesized through a facile one-pot hydrothermal route. The composite CuFe2O4-TiO2 photocatalysts with a heterojunction were then fabricated through a simple mixing and heating method. The transmission electron microscopy (TEM) images revealed the clear hollow structure of the catalyst, and the TiO2 nanoparticles were attached tightly on the surface of the microspheres. Crystal structures and surface chemical composition of the photocatalysts were confirmed by powder X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements. The band structure of the CuFe2O4-TiO2 photocatalyst was confirmed using Mott-Schottky measurements and UV-Vis absorption results. As expected, the CuFe2O4-TiO2 photocatalysts exhibited an enhanced photodegradation activity of methylene blue compared to bare CuFe2O4 and TiO2. A Z-scheme system was proposed and the efficient separation of photogenerated electron-hole pairs through the heterojunction resulted in the enhanced performance. This study provides an effective noble-metal-free and low-cost photocatalyst, and opens up a new synthesis strategy to construct other types of photocatalysts with morphology design. [ABSTRACT FROM AUTHOR]

Two new interpenetrated ThSi2networks, {[Ag4(bipy)4(ox)]·2OH·16H2O}n(1) and {[Ag2(dpb)2(ox)]·10H2O}n(2) (bipy = 4,4′-bipyridine, dpb = 1,4-di(pyridin-4-yl)benzeneand Na2ox = sodium oxalate), were constructed from bidentatepyridyl-based organic tectons incorporating ox auxiliary ligand. Interestingly,both 1and 2are 3D frameworks with thesame ThSi2topology but with substantial changes in theinterpenetration degrees, which are well controlled by employing thepyridyl-based ligands with different lengths. The thermal stabilitiesand photoluminescence behaviors of them were also discussed. [ABSTRACT FROM AUTHOR]

Lambda-cyhalothrin is a pyrethroid widely used in crop, fruit and vegetable production, but has potential health threats to human. Immunoassay is a cheap, rapid and facile method to detect lambda-cyhalothrin, yet wide application of this method still requires improvement in the construction of antigen. In this study, we developed a one-step lambda-cyhalothrin hapten synthesis that transformed the cyanide group in lambda-cyhalothrin to amide. Complete antigen was assembled by coupling the amide with succinic-anhydride-activated carrier proteins, and corresponding polyclonal antibodies were generated using Balb/c mice. Using antibody generated by the method in this paper, the competitive ELISA demonstrated the lowest detection limit of 3.772 μg/L for lambda-cyhalothrin, and no significant cross-reactivity for other pyrethroid pesticides was observed. All the results suggested we have established a more efficient technique of generating lambda-cyhalothrin antibody. Furthermore, since the activated proteins used in this study are highly controllable, we believe these proteins could potentially be the prototype of a series of standardized carrier proteins for the synthesis of complete antigens. Image 1 • A safe and high-yielding one-step lambda-cyhalothrin hapten synthesis strategy was developed. • A novel succinic anhydride activating technology was developed which provided the carrier proteins with more reactive sites. • The carrier protein activation method has provided a new solution to the poor-conjugation problems. [ABSTRACT FROM AUTHOR]

Dietary intake is the major route for the exposure of residents to short-chain chlorinated paraffins (SCCPs). SCCPs are classified as persistent organic pollutants (POPs) by the Stockholm Convention since May 2017. This study assessed the general population's dietary exposure to SCCPs through supermarket products. Five food categories, which included 40 food species, were collected from five supermarkets in April 2019. The SCCP concentrations in all food matrices varied between 58.6 and 1977 ng g−1 dry weight (dw), with the average and standard deviation (SD) value of 301 ± 379 ng g−1 dw. Generally, the SCCP concentrations in animal-origin food matrices were higher than those in plant-origin food matrices. The C 10 Cl 7 congeners were predominant among the congener groups of SCCPs. The proportion of C 10 congeners in the animal-origin food samples (29.8%) was lower than that in the plant-origin food samples (39.7%), and the C 13 congeners showed a contrasting result. The estimated daily intake (EDI) of SCCPs through dietary intake for the residents was 3109 ng kg−1 day−1, which is much lower than the standards of European Food Safety Authority (10 mg kg−1 day−1) for SCCPs. Risk assessment based on the supermarket foods indicated that SCCP exposure through dietary intake does not cause adverse effects to human health according to the margin of exposure (MOE). Image 1 • SCCP levels in animal food were three times higher than those in plant food. • SCCP concentrations were positively related to lipid content (p < 0.01). • C 10 Cl 7 congener groups were predominant in food samples. • SCCP exposure through dietary intake poses no adverse effects according to the NOAEL. [ABSTRACT FROM AUTHOR]