检索结果-南通市图书馆

Science Bulletin 2024年第2期69卷 159-162页

作者： Si-yuan Yu Yi-Li Liu Zheng Li Dechen Jiang Jing-Juan Xu hong-yuan chen Wei-Wei Zhao State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Nanoelectrodes have been shown to be powerful tools for nanoscopic research on single entities,deepening the understanding of heterogeneity and stochastics for single molecules,nanoparticles and cells[1–3].However,despite their importance,current nanoelectrode preparations are highly restrained to flame/electrochemical etching,metal sputtering,electrochemical deposition,etc.[3],resulting in a limited range of materials(mainly gold,platinum and carbon)for potential-resolved detection of redox-active species(Table S1 online).The enrichment of preparation methods to introduce novel materials and mechanisms should prove significant for the development of nanoelectrodes.

关键词： electrode deepening restrained

Aggregation-induced delayed electrochemiluminescence of organic dots in aqueous media

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Aggregate

Aggregate 2024年第1期5卷 167-174页

作者： Hang Gao Shen-Yu Shi Shu-MinWang Qian-Qian Tao Hui-Li Ma Jun Hu hong-yuan chen Jing-Juan Xu State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjingChina Key Laboratory of Flexible Electronics(KLOFE)and Institute of Advanced Materials(IAM) Nanjing Tech UniversityNanjingChina School of Life Science and Health Engineering Jiangnan UniversityWuxiChina

Full utilization of the excited species at both singlet states(1R*)and triplet states(3R*)is crucial to improving electrochemiluminescence(ECL)efficiency but is challenging for organic luminescent ***,an aggregation-induced delayed ECL(AIDECL)active organic dot(OD)containing a benzophenone acceptor and dimethylacridine donor is reported,which shows high ECL efficiency via reverse intersystem crossing(RISC)of non-emissive 3R*to emissive 1R*,overcoming the spin-forbidden radiative decay from 3R*.By introducing dual donor-acceptor pairs into luminophores,it is found that nonradiative pathway could be further suppressed via enhanced intermolecular weak interactions,and multiple spin-up conversion channels could be *** a consequence,the obtained OD enjoys a 6.8-fold higher ECL efficiency relative to the control AIDECL-active ***-crystal studies and theoretical calculations reveal that the enhanced AIDECL behaviors come from the acceleration of both radiative transition and *** work represents a major step towards purely organic,high-efficiency ECL dyes and a direction for the design of next-generation ECL dyes at the molecular level.

关键词： aggregation-induced delayed electrochemiluminescence benzophenone dimethylacridine organic dots reverse intersystem crossing

Bioanalysis in single cells: current advances and challenges

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2020年第5期63卷 564-588页

作者： hong-yuan chen State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Cells, basic units of living structures and functions, build up a complicated small world, and their order and complexity resemble a small universe. The detailed understanding and elucidation of the matter transport and energy conversion mechanisms within a single cell will expand our knowledge about the origin and evolution of life, the disease mechanisms and much more. In past decades, single-cell analysis has been rapidly and significantly improved and various methodologies have been developed to reveal the complexity of mass, energy, and information within single cells. In this review, we focused on the methods developed in recent years for single-cell analysis, including electrochemical method, optical method, and mass spectrometry method. We reviewed the recent advances and representative studies in this research field, and also discussed the strengths and limitations of each method. Finally, we presented the existing technical challenges and further directions for single-cell analysis.

关键词： bioanalysis single-cell electrochemistry single-cell optical analysis single-cell mass spectrometry

Nanoelectrochemical architectures for high-spatial-resolution single cell analysis

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2017年第10期60卷 1277-1284页

作者： Junyu Zhou Dechen Jiang hong-yuan chen State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

The analysis of single cells instead of cell populations is important for characterizing cellular heterogeneity and elucidating the cellular signalling pathways. Nanoelectrodes have emerged as an increasingly important tool for biomolecule analyses at the single-cell level with high spatial or temporal resolution. Various electrochemical methods, such as amperometry and scanning electrochemical microscopy(SECM), have been applied. Research to date has focused on the development of new nanoelectrochemical architectures, such as arrays, to achieve higher spatial resolution and faster analysis rates for single-cell analysis. In this review, the fabrication of these new nanoelectrochemical architectures and their applications in high spatial resolution single-cell analyses are discussed. The recent progress of Chinese researchers is highlighted.

关键词： nanoelectrochemical architectures single-cell analysis high spatial resolution high throughput

A robust watermarking algorithm based on QR factorization and DCT using quantization index modulation technique

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第8期13卷 573-584页

作者： hong-yuan chen Yue-sheng ZHU Communication and Information Security Lab Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China

We propose a robust digital watermarking algorithm for copyright protection.A stable feature is obtained by utilizing QR factorization and discrete cosine transform(DCT) techniques,and a meaningful watermark image is embedded into an image by modifying the stable feature with a quantization index modulation(QIM) *** combination of QR factorization,DCT,and QIM techniques guarantees the robustness of the ***,an embedding location selection method is exploited to select blocks with small modifications as the embedding *** can minimize the embedding distortion and greatly improve the imperceptibility of our *** standard images were tested and the experimental results were compared with those of other published *** results demonstrate that our proposed scheme can achieve not only better imperceptibility,but also stronger robustness against common signal processing operations and lossy compressions,such as filtering,noise addition,scaling,sharpening,rotation,cropping,and JPEG/JPEG2000 compression.

关键词： Digital watermarking QR factorization Quantization index modulation (QIM) Discrete cosine transform (DCT)

Electrochemiluminescence Analysis of Hydrogen Peroxide Using L012 Modified Electrodes

在线全文

学校读者我要写书评

暂无评论

Journal of Analysis and Testing 2020年第2期4卷 122-127页

作者： Yuling Wang Dechen Jiang hong-yuan chen State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

In this paper,a luminol analog,L012,with a high-electrochemiluminescence(ECL)illumination is covalently assembled at indium tin oxide(ITO)surface that exhibits the ECL response to hydrogen peroxide in the *** ITO slide is firstly functioned with amine group that react with glutaraldehyde to introduce aldehyde group at the *** the exposure to L012 with amine group,the reaction between the aldehyde group and the amine group results in the linkage of L012 at the electrode *** the presence of hydrogen peroxide,enhanced ECL from L012 at the electrode surface is observed that is linearly related with the concentration of hydrogen *** detection limit is determined to be 4.3μM(S/N=3).The successful establishment of ECL response to hydrogen peroxide using L012 modified electrode will provide a new functioned ECL surface for the future ECL imaging of hydrogen peroxide release from single cells.

关键词： Electrochemiluminescence L012 High ECL illumination Functioned surface Hydrogen peroxide

Emerging advances in plasmonic nanoassemblies for biosensing and cell imaging

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国化学快报:英文版 2023年第9期34卷 15-24页

作者： Jin Wang chen Wang Jing-Juan Xu Xing-Hua Xia hong-yuan chen College of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Integrating discrete plasmonic nanoparticles into assemblies can induce plasmonic coupling that produces collective plasmonic properties,which are not available for single *** analysis revealed that plasmonic coupling derived from assemblies could produce stronger electromagnetic field enhancement ***,plasmonic assemblies enable better performance in plasmon-based applications,such as enhanced fluorescence and Raman *** makes them hold great potential for trace analyte detection and ***,we focus on the recent advances in various plasmonic nanoassembles such as dimers,tetramers,and core-satellite structures,and discuss their applications in biosensing and cell *** fabrication strategies for self-assembled plasmonic nanostructures are described,including top-down strategies,self-assembly methods linked by DNA,ligand,polymer,amino acid,or proteins,and chemical overgrowth ***,their applications in biosensor and cell imaging based on dark-field imaging,surface-enhanced Raman scattering,plasmonic circular dichroism,and fluorescence imaging are ***,the remaining challenges and prospects are elucidated.

关键词： Plasmonic nanoasssembly Dark-field imaging Plasmonic circular dichroism Surface-enhanced Raman scattering Biosensing Cell imaging

真空紫外激光解吸/电离单细胞质谱成像装置的研制和调试

在线全文

学校读者我要写书评

暂无评论

应用化学 2024年第1期41卷 100-108页

作者：邢蕾牟含章潘建斌康斌徐静娟陈洪渊南京大学化学与化工学院生命分析化学国家重点实验室南京210023

开发同时具有亚微米分辨率以及高检测灵敏度的无基质质谱成像方法,对于可视化单细胞生物样品具有重要意义。在此,提出了真空紫外激光解吸/电离飞行时间质谱成像(VUVDI-ToFMSI)方法。通过调整基频光波长至777.7、403.22和255 nm,汞蒸气... 详细信息

开发同时具有亚微米分辨率以及高检测灵敏度的无基质质谱成像方法,对于可视化单细胞生物样品具有重要意义。在此,提出了真空紫外激光解吸/电离飞行时间质谱成像(VUVDI-ToFMSI)方法。通过调整基频光波长至777.7、403.22和255 nm,汞蒸气池中氩气气压至1100 Pa以及温度至240℃,获得接近13μJ/pulse的高强度VUV激光能量;同时,设计的同轴光路聚焦VUV激光至亚微米水平;另外,通过进一步调整偏转电场、离子聚焦电场以及反射电场的电负性以及电压等参数,离子的飞行路径得到矫正与优化。基于这种方法,实现了单个HeLa细胞中外源性药物亚甲基蓝(m/z 284.4)、内源性代谢物离子信号m/z 152.1以及m/z 81.1的纳米级成像(~500 nm/pixel),结果表明它们分别富集在细胞质、细胞核以及核仁内,证明了该方法在绘制单细胞不同区室内外源和内源性化学物质的高分辨以及高灵敏度的成像能力。该VUVDI-ToFMSI平台将为了解更多生物样本的精细结构与功能提供更完整、更深入的化学信息。

关键词：单细胞质谱成像真空紫外亚微米分辨

Measuring the number concentration of arbitrarily-shaped gold nanoparticles with surface plasmon resonance microscopy

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2016年第7期59卷 843-847页

作者： Xiang Wo Yashuang Luo Nongjian Tao Wei Wang hong-yuan chen State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical Engineering Nanjing University Nanjing 210023 China

Molar concentration of gold nanoparticles is one of the most critical parameters of gold colloids in order to develop their applications in sensing, diagnostics and nanomedicine. Previous methods often stand just for gold nanoparticles with regular shape and narrow size distribution. In the present work, we proposed an absolute quantification method that determined the molar concentration of gold nanoparticles with arbitrary shapes and polydisperse sizes. This approach involved the real time monitoring and counting of individual nanoparticles collision events, from which the quantification of molar concentration was achieved using a theoretical model consisting of Fiek＇s laws of diffusion and Stokes-Einstein equation. The determination of spherical gold nanoparticles concentration resulted in excellent agreement with traditional spectrometry method. It was further demonstrated that the present approach can be expanded to determine the molar concentration of gold nanoparticles with arbitrary shapes and poly-diversed distributions.

关键词： number concentration gold nanoparticles surface plasmon resonance microscopy

Cell mechanics and energetic costs of collective cell migration under confined microchannels

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第5期34卷 319-322页

作者： Xiao-hong Wang Yu Liu Bin Kang Jing-Juan Xu hong-yuan chen State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Department of Chemical and Chemical Engineering Hefei Normal UniversityHefei 230601China

Mechanical force between cells relates to many biological processes of cell *** cellular collective migration comes from cell-cell cooperation,and studying the intercellular mechanical properties helps elucidate collective cell ***,we studied cell-cell junctions,intercellular tensile force and the related cellular energetic costs in confined *** the intercellular force sensor,we found that cells adapt to different confinement environments by regulating intercellular force,and thereby the relationship between collective cell migration and cell-cell junction were *** the observation of cell orientation,actomyosin contractility,energetic costs,and glucose uptake,we can make a reasonable explanation of cell-force driven migration in different confined *** highly confined conditions,the intercellular force and energetic costs are greater,and the cell orientation is more *** collective migration behavior in confined spaces is closely related to the intercellular force and energetic costs,which is helpful to understand the collective migration behaviors in various confined spaces.

关键词： Cell mechanics Collective cell migration Cellular energetic costs Fluorescence probe Glucose uptake