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61.
Ying Wang Linxiang Cai Hui Li Hanhua Chen Tao Yang Yehong Tan Zijian Guo Xiaoyong Wang 《Angewandte Chemie (International ed. in English)》2023,62(42):e202309043
Drug resistance is a serious challenge for platinum anticancer drugs. Platinum complexes may get over the drug resistance via a distinct mechanism of action. Cholesterol is a key factor contributing to the drug resistance. Inhibiting cellular cholesterol synthesis and uptake provides an alternative strategy for cancer treatment. Platinum(IV) complexes FP and DFP with fenofibric acid as axial ligand(s) were designed to combat the drug resistance through regulating cholesterol metabolism besides damaging DNA. In addition to producing reactive oxygen species and active platinum(II) species to damage DNA, FP and DFP inhibited cellular cholesterol accumulation, promoted cholesterol efflux, upregulated peroxisome proliferator-activated receptor alpha (PPARα), induced caspase-1 activation and gasdermin D (GSDMD) cleavage, thus leading to both apoptosis and pyroptosis in cancer cells. The reduction of cholesterol significantly relieved the drug resistance of cancer cells. The double-acting mechanism gave the complexes strong anticancer activity in vitro and in vivo, particularly against cisplatin-resistant cancer cells. 相似文献
62.
Yanmin Hu Tingting Chao Yapeng Li Peigen Liu Tonghui Zhao Ge Yu Cai Chen Xiao Liang Huile Jin Shuwen Niu Wei Chen Dingsheng Wang Yadong Li 《Angewandte Chemie (International ed. in English)》2023,62(35):e202308800
Water electrolysis for H2 production is restricted by the sluggish oxygen evolution reaction (OER). Using the thermodynamically more favorable hydrazine oxidation reaction (HzOR) to replace OER has attracted ever-growing attention. Herein, we report a twisted NiCoP nanowire array immobilized with Ru single atoms (Ru1−NiCoP) as superior bifunctional electrocatalyst toward both HzOR and hydrogen evolution reaction (HER), realizing an ultralow working potential of −60 mV and overpotential of 32 mV for a current density of 10 mA cm−2, respectively. Inspiringly, two-electrode electrolyzer based on overall hydrazine splitting (OHzS) demonstrates outstanding activity with a record-high current density of 522 mA cm−2 at cell voltage of 0.3 V. DFT calculations elucidate the cooperative Ni(Co)−Ru−P sites in Ru1−NiCoP optimize H* adsorption, and enhance adsorption of *N2H2 to significantly lower the energy barrier for hydrazine dehydrogenation. Moreover, a self-powered H2 production system utilizing OHzS device driven by direct hydrazine fuel cell (DHzFC) achieve a satisfactory rate of 24.0 mol h−1 m−2. 相似文献
63.
Xingju Li Jiaqian Wang Qiao Yuan Xiangen Song Jiali Mu Yao Wei Li Yan Fanfei Sun Siquan Feng Yutong Cai Zheng Jiang Zhongkang Han Yunjie Ding 《Angewandte Chemie (International ed. in English)》2023,62(33):e202307570
Heterogeneous single-metal-site catalysts usually suffer from poor stability, thereby limiting industrial applications. Dual Pd1−Ru1 single-atom-sites supported on porous ionic polymers (Pd1−Ru1/PIPs) were constructed using a wetness impregnation method. The two isolated metal species in the form of a binuclear complex were immobilized on the cationic framework of PIPs through ionic bonds. Compared to the single Pd- or Ru-site catalyst, the dual single-atom system exhibits higher activity with 98 % acetylene conversion and near 100 % selectivity to dialkoxycarbonylation products, as well as better cycling stability for ten cycles without obvious decay. Based on DFT calculations, it was found that the single-Ru site exhibited a strong CO adsorption energy of −1.6 eV, leading to an increase in the local CO concentration of the catalyst. Notably, the Pd1−Ru1/PIPs catalyst had a much lower energy barrier of 2.49 eV compared to 3.87 eV of Pd1/PIPs for the rate-determining step. The synergetic effect between neighboring single sites Pd1 and Ru1 not only enhanced the overall activity, but also stabilized PdII active sites. The discovery of synergetic effects between single sites can deepen our understanding of single-site catalysts at the molecular level. 相似文献
64.
Yu-Xing Yao Dr. Xiang Chen Nan Yao Jin-Hui Gao Dr. Gang Xu Jun-Fan Ding Chun-Liang Song Dr. Wen-Long Cai Prof. Chong Yan Prof. Qiang Zhang 《Angewandte Chemie (International ed. in English)》2023,62(4):e202214828
Extreme fast charging (XFC) of high-energy Li-ion batteries is a key enabler of electrified transportation. While previous studies mainly focused on improving Li ion mass transport in electrodes and electrolytes, the limitations of charge transfer across electrode–electrolyte interfaces remain underexplored. Herein we unravel how charge transfer kinetics dictates the fast rechargeability of Li-ion cells. Li ion transfer across the cathode–electrolyte interface is found to be rate-limiting during XFC, but the charge transfer energy barrier at both the cathode and anode have to be reduced simultaneously to prevent Li plating, which is achieved through electrolyte engineering. By unlocking charge transfer limitations, 184 Wh kg−1 pouch cells demonstrate stable XFC (10-min charge to 80 %) which is otherwise unachievable, and the lifetime of 245 Wh kg−1 21700 cells is quintupled during fast charging (25-min charge to 80 %). 相似文献
65.
Xiao-Yu Li Dr. Tao Wang Yu-Chen Cai Zhao-Dong Meng Jing-Wen Nan Dr. Jin-Yu Ye Prof. Dr. Jun Yi Prof. Dr. Dong-Ping Zhan Prof. Dr. Na Tian Prof. Dr. Zhi-You Zhou Prof. Dr. Shi-Gang Sun 《Angewandte Chemie (International ed. in English)》2023,62(14):e202218669
Proton transfer is crucial for electrocatalysis. Accumulating cations at electrochemical interfaces can alter the proton transfer rate and then tune electrocatalytic performance. However, the mechanism for regulating proton transfer remains ambiguous. Here, we quantify the cation effect on proton diffusion in solution by hydrogen evolution on microelectrodes, revealing the rate can be suppressed by more than 10 times. Different from the prevalent opinions that proton transport is slowed down by modified electric field, we found water structure imposes a more evident effect on kinetics. FTIR test and path integral molecular dynamics simulation indicate that proton prefers to wander within the hydration shell of cations rather than to hop rapidly along water wires. Low connectivity of water networks disrupted by cations corrupts the fast-moving path in bulk water. This study highlights the promising way for regulating proton kinetics via a modified water structure. 相似文献
66.
Weiqing Xu Yu Wu Yuling Xu Dr. Xiaoli Cai Prof. Wenling Gu Prof. Chengzhou Zhu 《Angewandte Chemie (International ed. in English)》2023,62(47):e202308827
Enzymatic catalysis with high efficiency allows them a great prospect in metabolite monitoring in living cells. However, complex tumor microenvironments, such as acidity, H2O2, and hypoxia, are bound to disturb catalytic reactions for misleading results. Here, we report a spatially compartmentalized artificial organelle to correct intratumoral glucose analysis, where the zeolitic imidazolate framework-8 immobilized glucose oxidase-horseradish peroxidase cascade core and catalase-directed shell act as signal transduction and guarding rooms respectively. The acid-digested core and stable shell provide appropriate spaces to boost biocatalytic efficiency with good tolerability. Notably, the endogenous H2O2 is in situ decomposed to O2 by catalase, which not only overcomes the interference in signal output but also alleviates the hypoxic states to maximize glucose oxidation. The marked protective effect and biocompatibility render artificial organelles to correct the signal transduction for dynamic monitoring glucose in vitro and in vivo, achieving our goal of accurate intratumoral metabolite analysis. 相似文献
67.
Hongpu Huang Dr. Kai Liu Dr. Fulin Yang Junlin Cai Shupeng Wang Weizhen Chen Dr. Qiuxiang Wang Dr. Luhong Fu Prof. Zhaoxiong Xie Prof. Shuifen Xie 《Angewandte Chemie (International ed. in English)》2023,62(52):e202315752
Breaking atomic monogeneity of catalyst surfaces is promising for constructing synergistic active centers to cope with complex multi-step catalytic reactions. Here, we report a defect-derived strategy for creating surface phosphorous vacancies (P-vacancies) on nanometric Rh2P electrocatalysts toward drastically boosted electrocatalysis for alkaline hydrogen oxidation reaction (HOR). This strategy disrupts the monogeneity and atomic regularity of the thermodynamically stable P-terminated surfaces. Density functional theory calculations initially verify that the competitive adsorption behavior of Had and OHad on perfect P-terminated Rh2P{200} facets (p-Rh2P) can be bypassed on defective Rh2P{200} surfaces (d-Rh2P). The P-vacancies enable the exposure of sub-surface Rh atoms to act as exclusive H adsorption sites. Therein, the Had cooperates with the OHad on the peripheral P-sites to effectively accelerate the alkaline HOR. Defective Rh2P nanowires (d-Rh2P NWs) and perfect Rh2P nanocubes (p-Rh2P NCs) are then elaborately synthesized to experimentally represent the d-Rh2P and p-Rh2P catalytic surfaces. As expected, the P-vacancy-enriched d-Rh2P NWs catalyst exhibits extremely high catalytic activity and outstanding CO tolerance for alkaline HOR electrocatalysis, attaining 5.7 and 14.3 times mass activity that of p-Rh2P NCs and commercial Pt/C, respectively. This work sheds light on breaking the surface atomic monogeneity for the development of efficient heterogeneous catalysts. 相似文献
68.
Chao Duan Jianwei Zhang Shali Cai Junjun Xiang Prof. Xiaodi Yang Prof. Xike Gao 《European journal of organic chemistry》2023,26(5):e202201347
Linear polycyclic systems are promising candidates in the area of organic electronics. Herein, we present the syntheses of three azulene-indole (AzIn) fused polycyclic heteroaromatics (PHAs), AzIn - 1 , AzIn - 2 and DGAzIn , which have nitrogens and nonhexagonal rings simultaneously. The chemical structures, optical and electrochemical properties of three AzIn-based PHAs have been investigated, as well as their protonation behaviors with trifluoroacetic acid (TFA). All three AzIn-based PHAs exhibit narrow optical band gaps with moderate to good air stability, anti-Kasha emission and reversible stimuli-responsiveness. Furthermore, these straightforward and simple synthetic routes would provide a new entry for constructing novel azulene-embedded π-conjugates, especially for the seven-membered ring of azulene unit, wherein the regioselective transformation is not well developed. 相似文献
69.
Pengcheng Li Xiaohuan Chen Cui Guo Prof. Huijing Zou Ziyi Chen Bingjie Liu Wenjie Liang Prof. Jianfeng Cai Hai Xu 《欧洲无机化学杂志》2023,26(3):e202200576
One of the most critical and yet unsolved issues is the effective monitoring of multiple heavy metal ions in complex systems through their specific function in fluorescence detection. In this work, luminescence-active cadmium base metal-organic frameworks (Cd-MOFs) based on the planar and rigid π-conjugated structure ligand benzo-(1,2;3,4;5,6)-tris (thiophene-2’-carboxylic acid) (H3BTTC) was chosen. A series of sensing experiments demonstrated that the Cd-MOFs exhibits selective and sensitive response for Fe3+ and Eu3+ through fluorescence “turn off” and “antenna effect” respectively. In addition, the encapsulation of Eu3+ inside the Cd-MOFs (Eu3+@Cd-MOFs) led to an excellent probe with dual emission. To this end, a programmable fluorescence platform was developed to detect Fe3+ and Cu2+, in which the emission peaks of both the ligand and Eu3+ are completely quenched by Fe3+. The ratiometric detection of Cu2+ leads to a decrease in Eu3+ emission, while the ligand emission remains stable. To demonstrate the strategy, the fluorescence (Output) of Cd-MOFs, Eu3+@Cd-MOFs, and the analytes (Eu3+, Fe3+, and Cu2+, input) achieved elementary Boolean logic operations (OR, NOR, AND) and they constitute a logic fluorescent chemosensor to analyze Fe3+ and Cu2+ synchronously. 相似文献
70.
Yijing Wu Wenjun Zheng Canrong Chen Linyan Yang Ping Tong Yanhui Zhong Zian Lin Zongwei Cai 《Journal of separation science》2023,46(22):2300482
Here, an imine-linked-based spherical covalent organic framework (COF) was prepared at room temperature. The as-synthesized spherical COF served as an adsorbent in dispersive solid-phase extraction (dSPE), by its virtue of great surface area (1542.68 m2/g), regular distribution of pore size (2.95 nm), and excellent stability. Therefore, a simple and high-efficiency dispersive solid phase extraction method based on a spherical COF coupled with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established to determine aryl organophosphate esters in biological samples. This approach displayed favorable linearity in the range of 10.0–1000.0 ng/L (r > 0.9989), a high signal enhancement factor (58.8–181.8 folds) with low limits of detection (0.3–3.3 ng/L). Moreover, it could effectively eliminate complex matrix interference to accurately extract seven aryl organophosphate esters from mouse serum and tissue samples with spiked recoveries of 82.0%–117.4%. The as-synthesized spherical COF has been successfully applied in sample preparation. The dSPE-HPLC-MS/MS method based on a spherical COF has potential application to study the pollutants' metabolism in vivo. 相似文献