CHEMISTRY & BIODIVERSITY
·
2021
·Vol. 18
·期 10
·e2100244
·
IF 2.408
Du-Xin Jin,Jun-Fang He,Ke-Qin Zhang,Xue-Gang Luo,Tong-Cun Zhang
Hypericum attenuatum Choisy is a traditional Chinese herbal plant with multiple therapeutic effects. In this study, bioactivity-guided fractionation of Hypericum attenuatum Choisy extracts afforded three major flavonoids (including astragalin, guaijaverin and quercetin), which possessed α-Glucosidase inhibitory activity with IC 50 values of 33.90±0.68 μM, 17.23±0.75 μM and 31.90±0.34 μM, respectively. Circular dichroism analysis revealed that all the three compounds could interact with α-glucosidase by inducing conformational changes of the enzyme. Molecular docking results indicated that they could bind to the active site in α-glucosidase, and the binding force was driven mainly by hydrogen bond. Additionally, isobolographic analysis of the interactions between two compounds showed that all the combinations presented a synergistic α-glucosidase inhibitory effect at lower concentrations, and the combination between quercetin and guaijaverin or astragalin exhibited the best synergistic effect. This research might provide a theoretical basis for the application of Hypericum attenuatum Choisy in treating hyperglycemia.
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DOI
PubMed
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2022
·Vol. 223
·期 9
·2200022
·
IF 2.996
Lili Cai,Jiawei Lin,Mingyu Qiao,Jianwei Guo,Huatang Zhang,Sa Liu,Yong-Guang Jia
The multiregulation of aggregation-induced emission (AIE) that responds to external stimuli to finish multifunctions has become a focus of interest in biodiagnosis. Host–guest- recognition is an efficient strategy to introduce switchable, reversible, and other functional properties into AIE molecules. Herein, an amphiphilic tetraphenylethylene (TPE) derivative TPE-PEG is prepared via the simple amidation reaction and chosen as an AIE-based guest polymer. The aggregated state of TPE-PEG is altered and the fluorescence of TPE-PEG can be turned off in the presence of γ -cyclodextrins ( γ -CDs) due to the formation of host–guest complex between TPE units and γ -CDs. TPE units in the cavities of γ -CDs are released free and an aggregated state of TPE-PEG is restored via the guest competition epistasis of bile acid. Meanwhile, α -amylase can hydrolyze the host molecules of γ -CDs, resulting in an aggregated state of TPE-PEG again and turning the fluorescence on subtly. This reversible multiregulation of fluorescence may meet the multirequirements for the diagnosis in vivo due to the biological nature of α -amylase and bile acid.
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DOI
高影响因子
ACS Pharmacology & Translational Science
·
2024
·
IF 4.9
Jing-Jing Du,Shi-Hao Zhou,Jin Liu,Xing-Yuan Zhong,Ru-Yan Zhang,Wen-Xiang Zhao,Yu Wen,Zhen-Hong Su,Zheng Lu,Jun Guo
The tumor-associated antigen MUC1 is an attractive target for immunotherapy, however, its weak immunogenicity limits the induction of antitumor immune responses. To overcome this limitation, in this study, MUC1 glycopeptide was covalently linked with a diphtheria toxin-derived T-helper epitope (DT331–345). Subsequently, the resulting DT-MUC1 glycopeptide was physically mixed with natural killer T cell agonist αGalCer to explore their immunomodulatory synergy. Biological results demonstrated that compared to MUC1+αGalCer and DT-MUC1 groups, the specific IgG antibody titer of DT-MUC1+αGalCer group increased by 189- and 3-fold, respectively, indicating that the diphtheria toxin-derived T-helper epitope synergistically enhanced MUC1 immunogenicity with αGalCer. Moreover, the DT-MUC1+αGalCer vaccine induced potent cellular immune responses and significantly inhibited the growth of B16-MUC1 tumors in vivo. Furthermore, it was found that the anti-MUC1 IgG antibody titer induced by DT-MUC1+αGalCer was equivalent to that induced by palmitoylated DT-MUC1+αGalCer (P1-DT-MUC1+αGalCer) and significantly higher than that induced by doubly palmitoylated DT-MUC1+αGalCer (P2-DT-MUC1+αGalCer), suggesting that the easily synthesized DT-MUC1 may not require lipid chain modification and already possess good amphiphilicity. This is the first time that a diphtheria toxin-derived helper T-helper epitope was covalently linked to a glycopeptide antigen to enhance its immunogenicity, and this study may provide an effective vaccine design strategy for MUC1-targeted antitumor vaccines and offer novel insights into the design of fully synthetic peptide vaccines.
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DOI
高影响因子
GIANT
·
2024
·
IF 5.4
Xin Guan,Zhiheng Zhou,Xinzhen Fan,Wenchao Xu,Yijie Jin,Chuanzhuang Zhao
α -Methyl groups play significant roles in the regulation of water molecules within both small molecular systems and bio-macromolecular systems. Systematically studying the influence of α -methyl on the dynamics of water molecules within hydrogel systems is therefore worthwhile. In this study, we prepared a series of hydrogen-bonded (H-bonded) hydrogels with varying densities of α -methyl groups by copolymerizing methacrylamide (MAm) with its α -methyl-absent analogue, acrylamide (Am). Introducing a small amount of Am (≤6 mol%) into the polymer chain resulted in significant shifts in the viscoelasticity of the hydrogels. The hydrogels exhibit a “time-temperature- α -methyl equivalence”, meaning that introduction of α -methyl-absent monomer has effects similar to elevating temperature and prolonging observation time on the dynamic properties. Based on low-field nuclear magnetic resonance spectroscopy and Raman scattering, a “hydrophilic defects-assisted H-bonds dissociation” mechanism is proposed, depicting that the α -methyl-absent monomer can disturb the rearrangement of water molecules surrounding the polymer chain and accelerate chain dissociation. These findings enabled the copolymer hydrogels with functions such as fast self-healing and tunable interface adhesion.
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Ping Li,Shujuan Zhan,Lan Yao,Ya Xiong,Shuanghong Tian
Herein we reported the first example of preparing α-MnO 2 by selective acid etching from Mn-containing spinel. The defects, facet, and surface area of α-MnO 2 were cooperatively engineered by an all-in-one acid etching method to enhance the defect accessibility to the reactants. The obtained highly porous α-MnO 2 nanorods have rich defects of Mn 3+ (24.9%) and oxygen vacancies (31.4%), mainly active crystal facets of (110), and an ultrahigh surface area of 271.1 m 2 /g. With α-MnO 2 nanorods as the catalysts, more than 90.9% of 4-chlorophenol can be degraded within 12 min by catalytic ozonation in a wide work pH of 4.5–10.5. The experiments and DFT theory calculations reveal that α-MnO 2 with (110) facet promotes the adsorption and activation of ozone directly over the defects or indirectly over H 2 O adsorbed on the defects. Thus, more reactive oxygen species (e.g., •OH, •O 2 - , 1 O 2 , surface *O) are generated and get involved in pollutant degradation. This work provides a facile method to maximize the defect accessibility, and a deeper mechanistic study to understand the roles of the defects.
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Zhengyu Dong,Qian Zhang,Bor-Yann Chen,Junming Hong
A novel and high-efficiency Fe 3 O 4 -α-MnO 2 nanoflower-like catalyst was synthesized using a two-step hydrothermal method. The catalyst was used to activate persulfate (PS) to degrade bisphenol A (BPA) in aqueous phase. The mechanism of the Fe 3 O 4 -α-MnO 2 /PS system was investigated. X-ray photoelectron spectra and cyclic voltammograms showed that the mixed valence of Fe 3 O 4 -α-MnO 2 was favorable to electron transfer between Fe and Mn elements. Apparently, this process promoted the circulation of Fe 2+ /Fe 3+ and Mn 3+ /Mn 4+ , increasing the effectiveness of the catalyst to activate the PS. In addition, with ATR-FTIR analysis, the influence of phosphate confirmed the presence of OH groups on the Fe 3 O 4 -α-MnO 2 surface. Thus, these groups played crucial roles in the PS activation . Sulfate radicals were reacting species of great importance in BPA degradation. The degradation intermediates were also detected via GC–MS analysis, and the possible BPA degradation pathway was proposed.
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DOI
高影响因子
IONICS
·
2022
·Vol. 28
·期 10
·4769-4777
·
IF 2.961
Chang Xueyi,Qiu Yongfu,Cheng Zhiyu,Wang Xiaoting,Zhong Qingpeng,Huang Huizhen
To improve the specific capacitance of supercapacitor with bismuth oxide, this paper reports hollow nanosheet-assembled α-Bi 2 O 3 spheres prepared by solvothermal method as novel electrode materials. The electrochemical results show that the hollow nanosheet-assembled α-Bi 2 O 3 spheres exhibited a high electrochemical performance with a maximum specific capacitance of 1380.2 F g −1 at a current density of 1 A g −1 , which is the highest specific capacitance achieved to date with bismuth oxide as electrode material, and remarkable rate capability of 84.1% when the current density increased to as high as 15 A g −1 . The reasons for the high capacitance performance of the product are due to the monoclinic α-Bi 2 O 3 with a stable phase and more ion channels to transport and store ions, as well as the hollow spherical structure with porosity, which makes the material fully utilized. In a word, Bi 2 O 3 should be as a promising candidate towards high-performance electrode for pseudocapacitive supercapacitor.
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2020
·
IF 7.183
Xia Fu,Liping Zhu,Songmiao Liang,Yan Jin,Shuguang Yang
While polyvinylidene fluoride (PVDF) is widely used as a commercial UF membrane material, PVDF membrane often encounters fouling problems which significantly reduce the separation performance and service life of membrane. In this work, a special fluoro-contained polymer, sulfonated poly(α,β,β-trifluorostyrene) (SPTFS), is used to improve the hydrophilicity of PVDF membrane, thus to enhance the water flux and antifouling property of the membrane. PVDF membranes with different doping amount of SPTFS are prepared through conventional non-solvent induced phase separation method. Effects of doping SPTFS on the surface morphology , porosity, water contact angle and zeta potential of the prepared membranes are investigated. Compared with the pristine PVDF membrane, the SPTFS-doped membranes show improved hydrophilic property with enlarged finger-like pore structure , decreased water contact angle and higher negative surface charge density, as well as the increased filtration water flux. The enhanced anti-fouling property of the membrane is demonstrated by the cyclic filtration test and the in-situ monitoring of the adsorption and desorption of pollutants using a quartz crystal microbalance.
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高影响因子
Catalysts
·
2022
·Vol. 12
·期 6
·645
·
IF 4.501
Lian Sun,Qian Zhang,Qijie Liang,Wenbo Li,Xiangguo Li,Shenghua Liu,Jing Shuai
The counter electrode (CE) is an important and vital part of dye-sensitized solar cells (DSSCs). Pt CEs show high-performance in DSSCs using iodide-based electrolytes. However, the high cost of Pt CEs restricts their large-scale application in DSSCs and the development of Pt-free CE is expected. Here, α-Fe2O3/reduced graphene oxide (α-Fe2O3/RGO) composites are prepared as the Pt-free CE materials for DSSCs. A simple hydrothermal technique was used to disseminate the α-Fe2O3solid nanoparticles uniformly throughout the RGO surface. The presence of the α-Fe2O3nanoparticles increases the specific surface area of RGO and allows the composites to be porous, which improves the diffusion of liquid electrolyte into the CE material. Then, the electrocatalytic properties of CEs with α-Fe2O3/RGO, α-Fe2O3, RGO, and Pt materials are compared. The α-Fe2O3/RGO CE has a similar electrocatalytic performance to Pt CE, which is superior to those of the pure α-Fe2O3and RGO CEs. After being fabricated as DSSCs, the current–voltage measurements reveal that the DSSC based on α-Fe2O3/RGO CE has a power conversion efficiency (PCE) of 6.12%, which is 88% that of Pt CE and much higher than that of pure α-Fe2O3and pure RGO CEs. All the results show that this work describes a promising material for cost-effective, Pt-free CEs for DSSCs.
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DOI
高影响因子
Physica Status Solidi-Rapid Research Letters
·
2024
·
IF 2.5
Bo Zhang,Chengyang Niu,Wenlong Chu,Xuehao Guo,Xilong Zhou,Cheng Li,Xiulian Fan,Luwei Zou,Zhaofeng Wu,Yunzhang Lu,Fangping OuYang,Yu Zhou,Hongyan Zhang
Niobium-based oxides with wide bandgap and high dielectric constant show great potential in the applications of electronic and optoelectronic devices. Herein, the quasi-van der Waals epitaxial growth of 2D α-Nb 2 O 5 nanosheets is reported, in which the growth promoter of sulfur and alkali halides has been utilized to catalyze the ultrathin 2D growth. The relatively low Gibbs free energy of α-Nb 2 O 5 nanosheets can drive the ultrathin growth down to 30 nm on the c-Al 2 O 3 substrate by the transformation of T-Nb 2 O 5 powder sources without any doping effects, demonstrating the diverse α-Nb 2 O 5 nanostructure morphologies. The as-grown α-Nb 2 O 5 nanosheets are characterized with high crystalline quality and specific dominated growth plane, indicating the uniform dielectric properties. The metal–insulator–metal capacitor has confirmed the α-Nb 2 O 5 nanosheet with a high dielectric constant over 40. The dual promoters’ growth design strategy provides a universal synthesis method for the 2D nonlayered dielectric materials.
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yunxiao Zhang,Qingxiang Cao,Xuelian Wu,Yonghao Xiao,Aiyun Meng,Qitao Zhang,Yuxiang Yu,Wei-De Zhang
Establishing effective non-platinum active sites on polymeric carbon nitride (PCN) remains a great demanding to achieve highly efficient photocatalytic hydrogen generation performance. Modification with molecular complex catalysts on PCN skeletons has been demonstrated as a promising strategy. Herein, hybrid photocatalytic material was successfully synthesized by modifying PCN with copper molecular ligand ( CuL, Schiff-based copper complex) via π-π stacking. Interestingly, atomically dispersed Cu is formed in CuL/PCN. Compared to PCN, the π-π stacking in CuL/PCN is beneficial for facilitating the migration of photogenerated electrons from PCN to CuL . Furthermore, photo-redox ability of the atomically dispersed Cu is regulated by the ligand (Schiff base) in CuL and the introduction of CuL provides abundant active sites to capture the photogenerated electrons, whereby the reductive reaction of H 2 O/H + to H 2 for CuL/PCN was significantly promoted. Consequently, an optimal hydrogen evolution rate of 15.90 μmol·h −1 was obtained on 3CuL/PCN, which was 2.02 times higher than that of 3.0 wt% Pt/PCN (7.86 μmol·h −1 ). More importantly, the hybrid material exhibits an outstanding conversion efficiency (90 %) and selectivity (99 %) for α-methylation of ketones by making full use of the in-situ generated H species and photogenerated holes under visible light irradiation.
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DOI
高影响因子
Molecular Catalysis
·
2018
·
IF 0
Peipei Tao,Xinhuan Lu,Haifu Zhang,Run Jing,Fengfeng Huang,Sha Wu,Dan Zhou,Qinghua Xia
CoO x species is firstly introduced onto MOR (Mordenite) by impregnation with microwave heating to catalyze the epoxidation of α-pinene with air. The obtained samples have been characterized by X-ray diffraction, FTIR, SEM, TEM, BET surface area, porosity by N 2 adsorption. 7%CoO x /MOR catalyst exhibits remarkably higher activity and selectivity in the epoxidation of α-pinene than that prepared by traditional heating impregnation. The epoxidation conversion of α-pinene over 7%CoO x /MOR prepared by microwave heating reaches 92.7 mol% in 4 h at 90 °C, which is nearly 1.5 times that of the catalyst by traditional impregnation. This is due to the fact that CoO x nanoparticles are produced by microwave heating and uniformly dispersed on MOR.
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DOI
危险品化学品经营许可证（带存储）