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991.
992.
Shuai Zhang Hancheng Qin Shuwen Cheng Yue Zhang Nan Gao Prof. Meining Zhang 《Angewandte Chemie (International ed. in English)》2023,62(16):e202300083
Reactive oxygen species (ROS)-based therapeutic strategies play an important role in cancer treatment. However, in situ, real-time and quantitative analysis of intracellular ROS in cancer treatment for drug screening is still a challenge. Herein we report one selective hydrogen peroxide (H2O2) electrochemical nanosensor, which is prepared by electrodeposition of Prussian blue (PB) and polyethylenedioxythiophene (PEDOT) onto carbon fiber nanoelectrode. With the nanosensor, we find that the level of intracellular H2O2 increases with NADH treatment and that increase is dose-dependent to the concentration of NADH. High-dose of NADH (above 10 mM) can induce cell death and intratumoral injection of NADH is validated for inhibiting tumor growth in mice. This study highlights the potential of electrochemical nanosensor for tracking and understanding the role of H2O2 in screening new anticancer drug. 相似文献
993.
Shuai Zhao Prof. Shaohua Zhang Huijun Hu Yangchang Cheng Kexuan Zou Prof. Jie Song Dr. Jinqi Deng Prof. Lele Li Prof. Xiao-Bing Zhang Prof. Guoliang Ke Prof. Jiashu Sun 《Angewandte Chemie (International ed. in English)》2023,62(24):e202303121
Mature microRNAs (miRNAs) in extracellular vesicles (EVs) are involved in different stages of cancer progression, yet it remains challenging to precisely detect mature miRNAs in EVs due to the presence of interfering RNAs (such as longer precursor miRNAs, pre-miRNAs) and the low abundance of tumor-associated miRNAs. By leveraging the size-selective ability of DNA cages and polyethylene glycol (PEG)-enhanced thermophoretic accumulation of EVs, we devised a DNA cage-based thermophoretic assay for highly sensitive, selective, and in situ detection of mature miRNAs in EVs with a low limit of detection (LoD) of 2.05 fM. Our assay can profile EV mature miRNAs directly in serum samples without the interference of pre-miRNAs and the need for ultracentrifugation. A clinical study showed that EV miR-21 or miR-155 had an overall accuracy of 90 % for discrimination between breast cancer patients and healthy donors, which outperformed conventional molecular probes detecting both mature miRNAs and pre-miRNAs. We envision that our assay can advance EV miRNA-based diagnosis of cancer. 相似文献
994.
Dr. Huanhuan Shi Prof. Mengmeng Li Shuai Fu Dr. Christof Neumann Dr. Xiaodong Li Dr. Wenhui Niu Yunji Lee Prof. Mischa Bonn Dr. Hai I. Wang Prof. Andrey Turchanin Dr. Ali Shaygan Nia Dr. Sheng Yang Prof. Xinliang Feng 《Angewandte Chemie (International ed. in English)》2023,62(28):e202303929
Two-dimensional van der Waals heterostructures (2D vdWHs) have recently gained widespread attention because of their abundant and exotic properties, which open up many new possibilities for next-generation nanoelectronics. However, practical applications remain challenging due to the lack of high-throughput techniques for fabricating high-quality vdWHs. Here, we demonstrate a general electrochemical strategy to prepare solution-processable high-quality vdWHs, in which electrostatic forces drive the stacking of electrochemically exfoliated individual assemblies with intact structures and clean interfaces into vdWHs with strong interlayer interactions. Thanks to the excellent combination of strong light absorption, interfacial charge transfer, and decent charge transport properties in individual layers, thin-film photodetectors based on graphene/In2Se3 vdWHs exhibit great promise for near-infrared (NIR) photodetection, owing to a high responsivity (267 mA W−1), fast rise (72 ms) and decay (426 ms) times under NIR illumination. This approach enables various hybrid systems, including graphene/In2Se3, graphene/MoS2 and graphene/MoSe2 vdWHs, providing a broad avenue for exploring emerging electronic, photonic, and exotic quantum phenomena. 相似文献
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四氯四溴荧光素(TBTCF)能够与氯化银胶体在pH 4.33时发生灵敏的沉淀吸附反应,根据该反应颜色变化,应用光吸收比差法建立了痕量氯离子测定的新方法。实验表明盐度和温度对反应体系影响不明显。Cl-浓度在0.09~9.0 mg/L范围与光吸收比差(△Ar)呈线性关系,方法检出限为0.03μg/mL。通过对三种地面水体Cl-的分析,加标回收率为96.2%~104%,测定结果与离子色谱法相吻合。该方法具有成本低、选择性好、灵敏度高等特点,适用于现场在线检测以及海水、高温水体中氯离子的直接定量测定。 相似文献
998.
利用同余理论和多项式理论研究二项式系数幂和序列在模p2下的同余性质,得到了一些非平凡结果.为进一步研究二项式系数幂和序列的多项式递推公式提供有利的工具. 相似文献
999.
根据同余理论并利用二项式系数幂和序列在模p下具有周期性的事实,提出一种求解递推公式的方法,从理论上证明其可行性.使得求解和验证二项式系数幂和序列递推公式具有完备的理论基础. 相似文献
1000.
Shuai Zhang Yongjin Wang Prof. Hanchu Huang Prof. Derong Cao 《Angewandte Chemie (International ed. in English)》2023,62(37):e202308524
The ability to extend the polymerizations of thiyl radical propagation to be regulated by existing controlled methods would be highly desirable, yet remained very challenging to achieve because the thiyl radicals still cannot be reversibly controlled by these methods. In this article, we reported a novel strategy that could enable the radical ring-opening polymerization of macrocyclic allylic sulfides, wherein propagating specie is thiyl radical, to be controlled by reversible addition–fragmentation chain transfer (RAFT) agents. The key to the success of this strategy is the propagating thiyl radical can undergo desulfurization with isocyanide and generate a stabilized alkyl radical for reversible control. Systematic optimization of the reaction conditions allowed good control over the polymerization, leading to the formation of polymers with well-defined architectures, exemplified by the radical block copolymerization of macrocyclic allylic sulfides and vinyl monomers and the incorporation of sequence-defined segments into the polymer backbone. This work represents a significant step toward directly enabling the polymerizations of heteroatom-centered radical propagation to be regulated by existing reversible-deactivation radical polymerization techniques. 相似文献