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Ternary metal sulfides have excellent light absorption properties, but their high recombination rate of photo generated carriers limits their practical application. To address this problem, this work constructed a novel nanoflower−like AgIn 5 S 8 /ZnIn 2 S 4 heterojunction and explored its removal performance for Cr(VI) in water. AgIn 5 S 8 was prepared by the solvothermal method, whereas ZnIn 2 S 4 and AgIn 5 S 8 /ZnIn 2 S 4 heterojunction was synthesized via the hydrothermal method. The morphological characteristics of AgIn 5 S 8 /ZnIn 2 S 4 heterojunction showed that the AgIn 5 S 8 particles uniformly distributed on the surface of ZnIn 2 S 4 with a flower like structure. The obtained 10% AgIn 5 S 8 /ZnIn 2 S 4 exhibited a higher specific surface area (75.07 m2/g) than AgIn 5 S 8 (20.91 m2/g) and ZnIn 2 S 4 (58.30 m2/g), with the maximum Cr(VI) removal efficiency of 88.5% at an initial concentration of 20 mg/L. The photocatalytic reduction of Cr(VI) by AgIn 5 S 8 /ZnIn 2 S 4 conformed to the pseudo-first-order kinetic model. The superoxide radicals (·O 2 −) and photogenerated electrons (e−) were identified as the major active substances for Cr(VI) photoreduction according to the electron paramagnetic resonance (EPR) and free radical trapping experiments. The Mott−Schottky analysis demonstrated that the band structures of AgIn 5 S 8 and ZnIn 2 S 4 were compatible. Density functional theory (DFT) calculations showed that AgIn 5 S 8 /ZnIn 2 S 4 heterojunction enhanced the separation efficiency of photogenerated carriers through an internal electric field (IEF). These results demonstrate that type–II AgIn 5 S 8 /ZnIn 2 S 4 heterojunctions have the potential for effective removal of Cr(VI) in wastewater under visible light irradiation. [Display omitted] • A type–II AIS/ZIS heterojunction with high photocatalytic activity was synthesized. • The 10% AIS/ZIS showed higher photocatalytic reduction ability for Cr(VI). • O 2 - and e- were the primary active species in the photoreduction of Cr(VI). • DFT showed electrons migrated from ZnIn 2 S 4 to AgIn 5 S 8 through the interface. [ABSTRACT FROM AUTHOR]

Microdialysis sampling coupled with liquid chromatography and electrochemical detection (LC–ECD) was developed and applied to study the interaction of 6-Mercaptopurine (6-MP) with bovine serum albumin (BSA). In the LC–ECD, the multi-wall carbon nanotubes fuctionalized with carboxylic groups modified electrode (MWNT-COOH CME) was used as the working electrode for the determination of 6-MP. The results indicated that this chemically modified electrode (CME) exhibited efficiently electrocatalytic oxidation for 6-MP with relatively high sensitivity, stability and long-life. The peak currents of 6-MP were linear to its concentrations ranging from 4.0×10−7 to 1.0×10−4 mol l−1 with the calculated detection limit (S/N=3) of 2.0×10−7 mol l−1. The method had been successfully applied to assess the association constant (K) and the number of the binding sites (n) on a BSA molecular, which calculated by Scatchard equation, were 3.97×103 mol−1 l and 1.51, respectively. This method provided a fast, sensible and simple technique for the study of drug–protein interactions. [Copyright &y& Elsevier]

Abstract: A convenient approach to 3-sec-alkyl substituted indoles was developed via palladium-catalyzed addition of arylboronic acids to vinylogous imines generated in situ from sulfonylindoles under mild conditions. [Copyright &y& Elsevier]

Cardiovascular disease (CVD) is a serious disease with a high incidence rate and mortality. Inflammation is closely related to the occurrence of CVDs. As an essential medicine of promoting blood circulation and removing blood stasis in China, Salvia miltiorrhiza Bunge (Danshen) is widely used to treat CVDs due to its anti-inflammatory and cardiovascular protective effects. Salvianolic acids are the most abundant component in the water extract of S. miltiorrhiza , which has a significant effect on the treatment of CVDs. However, due to the complex composition of salvianolic acids, the active molecules and their underlying mechanisms have not been fully explored. The present study aims to isolate and identify salvianolic acids from Danshen with anti-inflammatory activity and explore the potential mechanisms of isolates. The structures of isolated salvianolic acids were elucidated by UV, IR, NMR, MS and electronic circular dichroism (ECD) calculations. Then anti-inflammatory activities of isolates were screened out by the zebrafish inflammation models. The most active compound was further used to explore the anti-inflammatory mechanisms on LPS-stimulated RAW 264.7 cells. The key inflammatory cytokines IL-6 and TNF-α were measured by enzyme-linked immunosorbent assay (ELISA). The protein expression levels of STAT3, p-STAT3 (Tyr705), NF-κB p65, IκBα, p-IκBα (Ser32) and α7nAchR were determined by Western blotting. The nuclear translocation of p-STAT3 (Tyr705) and NF-κB p65 was evaluated by immunofluorescence assays. Finally, the in vivo anti-inflammatory mechanisms were investigated by observation of neutrophil migration, H&E staining, survival analysis and quantitative PCR (Q-PCR) in LPS-microinjected zebrafish. Two new and four known compounds were isolated from Danshen. Among them, isosalvianolic acid A-1 (C1) and ethyl lithospermate (C5) inhibited neutrophil migrations in three zebrafish inflammation models and C1 with the best activities decreased the secretion of IL-6 and TNF-α and inhibited the expression level of p-IκBα (Ser32) in LPS stimulated RAW 264.7 cells. In addition, C1 also reduced the nuclear translocation of NF-κB p65 and p-STAT3 (Tyr705). Moreover, C1 significantly upregulated the protein expression of α7nAchR, and the knockdown of α7nAchR counteracted the effects of C1 on the production of IL-6 and TNF-α and the expression levels of p-STAT3 (Tyr705), NF-κB p65 and p-IκBα (Ser32). In vivo experiments, C1 decreased the migration and infiltration of inflammatory cells, increased the survival ratio and inhibited the mRNA level of IL-6, TNF-α, STAT3, NF-κB and IκBα in LPS-microinjected zebrafish. Two new and four known compounds were isolated from Danshen. Among them, C1 exerted anti-inflammatory activities by activating α7nAchR signaling and subsequently inhibiting STAT3 and NF-κB pathways. This study provided evidence for the clinical application of Danshen and contributed to the development of C1 as a novel in the treatment of cardiovascular disease. [Display omitted] • Isolation and identification 2 new and 4 known salvianolic acids from Salvia miltiorrhiza Bunge. • Anti-Inflammatory activity of 6 salvianolic acids were evaluated by zebrafish inflammation models. • Isosalvianolic acid A-1 as an α7nAchR activator exerts anti-inflammatory effects by inhibiting STAT3 and NF-κB pathways. [ABSTRACT FROM AUTHOR]