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Cui L, Zhang L, Li Z, Jing Z, Huang L, Zeng H. Giant enhancement of fluorescence resonance energy transfer based on nanoporous gold with small amount of residual silver. NANOTECHNOLOGY 2024; 35:195709. [PMID: 38241734 DOI: 10.1088/1361-6528/ad20a0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 01/19/2024] [Indexed: 01/21/2024]
Abstract
Fluorescence resonance energy transfer (FRET) was found strongly enhanced by plasmon resonance. In this work, Nanoporous Gold with small amount of residual silver was used to form nanoporous gold/organic molecular layer compound with PSS and PAH. The ratio of its specific gold and silver content is achieved by controlling the time of its dealloying. Layered films of polyelectrolyte multilayers were assembled between the donor-acceptor pairs and NPG films to control distance. The maximum of FRET enhancement of 80-fold on the fluorescence intensity between the donor-acceptor pairs (CFP-YFP) is observed at a distance of ∼10.5 nm from the NPG film. This Nanoporous Gold with small amount of residual silver not only enhanced FRET 4-fold more than nanoporous gold of only gold content almost, but also effectively realized the regulation of FRET enhancement. The ability to precisely measure and regulate the enhancement of FRET enables the rational selection of plasmonic nanotransducer dimensions for the particular biosensing application.
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Affiliation(s)
- Lianmin Cui
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, People's Republic of China
| | - Ling Zhang
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, People's Republic of China
| | - Zhexiao Li
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, People's Republic of China
| | - Zhiyu Jing
- School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, People's Republic of China
| | - Luyi Huang
- CAS Key Laboratory of Nanophotonic Materials and Devices & Key Laboratory of Nanodevices and Applications, i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences, Suzhou 215123, People's Republic of China
| | - Heping Zeng
- Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, People's Republic of China
- Chongqing Key Laboratory of Precision Optics, Chongqing Institute of East China Normal University, Chongqing, People's Republic of China
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Gao T, Shen Y, Gu L, Zhang Z, Yuan W, Xi W. Surface-strain-enhanced oxygen dissociation on gold catalysts. RSC Adv 2023; 13:22710-22716. [PMID: 37502824 PMCID: PMC10369369 DOI: 10.1039/d3ra03781a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 07/19/2023] [Indexed: 07/29/2023] Open
Abstract
The excellent low-temperature oxidation performance and stability of nanogold catalysts have attracted significant interest. However, the main active source of the low-temperature oxidation of gold remains to be determined. In situ electron microscopy and mass spectrometry results show that nitrogen is oxidized, and the catalyst surface undergoes reconstruction during the process. Strain analysis of the catalyst surface and first-principles calculations show that the tensile strain of the catalyst surface affects the oxidation performance of gold catalysts by enhancing the adsorption ability and dissociation of O2. The newly formed active oxygen atoms on the gold surface act as active sites in the nitrogen oxidation reaction, significantly enhancing the oxidation ability of gold catalysts. This study provides evidence for the dissociation mechanism of oxygen on the gold surface and new design concepts for improving the oxidation activity of gold catalysts and nitrogen activation.
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Affiliation(s)
- Tianqi Gao
- Center for Electron Microscopy, Tianjin Key Laboratory of Advanced Functional Porous Materials, Institute for New Energy Materials and Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology Tianjin 300384 China
| | - Yongli Shen
- Center for Electron Microscopy, Tianjin Key Laboratory of Advanced Functional Porous Materials, Institute for New Energy Materials and Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology Tianjin 300384 China
| | - Lin Gu
- Center for Electron Microscopy, Tianjin Key Laboratory of Advanced Functional Porous Materials, Institute for New Energy Materials and Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology Tianjin 300384 China
| | - Zhaocheng Zhang
- Center for Electron Microscopy, Tianjin Key Laboratory of Advanced Functional Porous Materials, Institute for New Energy Materials and Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology Tianjin 300384 China
| | - Wenjuan Yuan
- Center for Electron Microscopy, Tianjin Key Laboratory of Advanced Functional Porous Materials, Institute for New Energy Materials and Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology Tianjin 300384 China
| | - Wei Xi
- Center for Electron Microscopy, Tianjin Key Laboratory of Advanced Functional Porous Materials, Institute for New Energy Materials and Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology Tianjin 300384 China
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Wittstock G, Bäumer M, Dononelli W, Klüner T, Lührs L, Mahr C, Moskaleva LV, Oezaslan M, Risse T, Rosenauer A, Staubitz A, Weissmüller J, Wittstock A. Nanoporous Gold: From Structure Evolution to Functional Properties in Catalysis and Electrochemistry. Chem Rev 2023; 123:6716-6792. [PMID: 37133401 DOI: 10.1021/acs.chemrev.2c00751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Nanoporous gold (NPG) is characterized by a bicontinuous network of nanometer-sized metallic struts and interconnected pores formed spontaneously by oxidative dissolution of the less noble element from gold alloys. The resulting material exhibits decent catalytic activity for low-temperature, aerobic total as well as partial oxidation reactions, the oxidative coupling of methanol to methyl formate being the prototypical example. This review not only provides a critical discussion of ways to tune the morphology and composition of this material and its implication for catalysis and electrocatalysis, but will also exemplarily review the current mechanistic understanding of the partial oxidation of methanol using information from quantum chemical studies, model studies on single-crystal surfaces, gas phase catalysis, aerobic liquid phase oxidation, and electrocatalysis. In this respect, a particular focus will be on mechanistic aspects not well understood, yet. Apart from the mechanistic aspects of catalysis, best practice examples with respect to material preparation and characterization will be discussed. These can improve the reproducibility of the materials property such as the catalytic activity and selectivity as well as the scope of reactions being identified as the main challenges for a broader application of NPG in target-oriented organic synthesis.
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Affiliation(s)
- Gunther Wittstock
- Carl von Ossietzky University of Oldenburg, School of Mathematics and Science, Institute of Chemistry, D-26111 Oldenburg, Germany
| | - Marcus Bäumer
- University of Bremen, Institute for Applied and Physical Chemistry, 28359 Bremen, Germany
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
| | - Wilke Dononelli
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
- University of Bremen, Bremen Center for Computational Materials Science, Hybrid Materials Interfaces Group, Am Fallturm 1, Bremen 28359, Germany
| | - Thorsten Klüner
- Carl von Ossietzky University of Oldenburg, School of Mathematics and Science, Institute of Chemistry, D-26111 Oldenburg, Germany
| | - Lukas Lührs
- Hamburg University of Technology, Institute of Materials Physics and Technology, 21703 Hamburg, Germany
| | - Christoph Mahr
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
- University of Bremen, Institute of Solid State Physics, Otto Hahn Allee 1, 28359 Bremen, Germany
| | - Lyudmila V Moskaleva
- University of the Free State, Department of Chemistry, P.O. Box 339, Bloemfontein 9300, South Africa
| | - Mehtap Oezaslan
- Technical University of Braunschweig Institute of Technical Chemistry, Technical Electrocatalysis Laboratory, Franz-Liszt-Strasse 35a, 38106 Braunschweig, Germany
| | - Thomas Risse
- Freie Universität Berlin, Institute of Chemistry and Biochemistry, Arnimallee 22, 14195 Berlin, Germany
| | - Andreas Rosenauer
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
- University of Bremen, Institute of Solid State Physics, Otto Hahn Allee 1, 28359 Bremen, Germany
| | - Anne Staubitz
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
- University of Bremen, Institute for Organic and Analytical Chemistry, Leobener Strasse 7, D-28359 Bremen, Germany
| | - Jörg Weissmüller
- Hamburg University of Technology, Institute of Materials Physics and Technology, 21703 Hamburg, Germany
- Helmholtz-Zentrum Hereon, Institute of Materials Mechanics, 21502 Geesthacht, Germany
| | - Arne Wittstock
- University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany
- University of Bremen, Institute for Organic and Analytical Chemistry, Leobener Strasse 7, D-28359 Bremen, Germany
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Wang X, Bai J, Zhang M, Chen Y, Fan L, Yang Z, Zhang J, Guan R. A Comparison between Porous to Fully Dense Electrodeposited CuNi Films: Insights on Electrochemical Performance. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:491. [PMID: 36770452 PMCID: PMC9919823 DOI: 10.3390/nano13030491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/17/2023] [Accepted: 01/22/2023] [Indexed: 06/18/2023]
Abstract
Nanostructuring of metals is nowadays considered as a promising strategy towards the development of materials with enhanced electrochemical performance. Porous and fully dense CuNi films were electrodeposited on a Cu plate by electrodeposition in view of their application as electrocatalytic materials for the hydrogen evolution reaction (HER). Porous CuNi film were synthesized using the hydrogen bubble template electrodeposition method in an acidic electrolyte, while fully dense CuNi were electrodeposited from a citrate-sulphate bath with the addition of saccharine as a grain refiner. The prepared films were characterized chemically and morphologically by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The Rietveld analysis of the XRD data illustrates that both CuNi films have a nanosized crystallite size. Contact angle measurements reveal that the porous CuNi film exhibits remarkable superhydrophobic behavior, and fully dense CuNi film shows hydrophilicity. This is predominately ascribed to the surface roughness of the two films. The HER activity of the two prepared CuNi films were investigated in 1 M KOH solution at room temperature by polarization measurements and electrochemical impedance spectroscopy (EIS) technique. Porous CuNi exhibits an enhanced catalysis for HER with respect to fully dense CuNi. The HER kinetics for porous film is processed by the Volmer-Heyrovsky reaction, whereas the fully dense counterpart is Volmer-limited. This study presents a clear comparison of HER behavior between porous and fully dense CuNi films.
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Affiliation(s)
- Xuejiao Wang
- School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China
| | - Jingyuan Bai
- School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China
| | - Meilin Zhang
- School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China
| | - Yuxi Chen
- Key Laboratory of Near-Net Forming of Light Metals of Liaoning Province, Dalian Jiaotong University, Dalian 116028, China
- Engineering Research Center of Continuous Extrusion, Ministry of Education, Dalian Jiaotong University, Dalian 116028, China
| | - Longyi Fan
- Key Laboratory of Near-Net Forming of Light Metals of Liaoning Province, Dalian Jiaotong University, Dalian 116028, China
- Engineering Research Center of Continuous Extrusion, Ministry of Education, Dalian Jiaotong University, Dalian 116028, China
| | - Zhou Yang
- Key Laboratory of Near-Net Forming of Light Metals of Liaoning Province, Dalian Jiaotong University, Dalian 116028, China
- Engineering Research Center of Continuous Extrusion, Ministry of Education, Dalian Jiaotong University, Dalian 116028, China
| | - Jin Zhang
- Key Laboratory of Near-Net Forming of Light Metals of Liaoning Province, Dalian Jiaotong University, Dalian 116028, China
- Engineering Research Center of Continuous Extrusion, Ministry of Education, Dalian Jiaotong University, Dalian 116028, China
| | - Renguo Guan
- Key Laboratory of Near-Net Forming of Light Metals of Liaoning Province, Dalian Jiaotong University, Dalian 116028, China
- Engineering Research Center of Continuous Extrusion, Ministry of Education, Dalian Jiaotong University, Dalian 116028, China
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Henkelmann G, Waldow D, Liu M, Lührs L, Li Y, Weissmüller J. Self-Detachment and Subsurface Densification of Dealloyed Nanoporous Thin Films. NANO LETTERS 2022; 22:6787-6793. [PMID: 35952308 PMCID: PMC9413411 DOI: 10.1021/acs.nanolett.2c02666] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Experiment shows thin films of dealloyed nanoporous gold (NPG) spontaneously detaching from massive gold base layers. NPG can also densify near its external surface. This is naturally reproduced by kinetic Monte Carlo (KMC) simulation of dealloying and coarsening and so appears generic for nanoscale network materials evolving by surface diffusion. Near the porous layer's external surface and near its interface with the base layer, gradients in the depth-profile of a laterally averaged mean surface curvature provide driving forces for diffusion and cause divergences of the net fluxes of matter, leading to accretion/densification or to erosion/disconnection. As a toy model, the morphology evolution of substrate-supported nanopillars by surface diffusion illustrates and confirms our considerations. Contrary to cylindrical nanowires, the ligaments in nanoporous materials exhibit pre-existing gradients in the mean curvature. The Plateau-Rayleigh long-wavelength stability criterion is then not applicable and the disconnection accelerated.
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Affiliation(s)
- Gideon Henkelmann
- Institute
of Materials Physics and Technology, Hamburg
University of Technology, 21073 Hamburg, Germany
| | - Diana Waldow
- Institute
of Materials Physics and Technology, Hamburg
University of Technology, 21073 Hamburg, Germany
| | - Maowen Liu
- Institute
of Materials Physics and Technology, Hamburg
University of Technology, 21073 Hamburg, Germany
- Institute
of Materials Mechanics, Helmholtz-Zentrum
Hereon, 21502 Geesthacht, Germany
| | - Lukas Lührs
- Institute
of Materials Physics and Technology, Hamburg
University of Technology, 21073 Hamburg, Germany
| | - Yong Li
- Institute
of Materials Physics and Technology, Hamburg
University of Technology, 21073 Hamburg, Germany
- Institute
of Materials Mechanics, Helmholtz-Zentrum
Hereon, 21502 Geesthacht, Germany
| | - Jörg Weissmüller
- Institute
of Materials Physics and Technology, Hamburg
University of Technology, 21073 Hamburg, Germany
- Institute
of Materials Mechanics, Helmholtz-Zentrum
Hereon, 21502 Geesthacht, Germany
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Hassan MH, Vyas C, Grieve B, Bartolo P. Recent Advances in Enzymatic and Non-Enzymatic Electrochemical Glucose Sensing. SENSORS (BASEL, SWITZERLAND) 2021; 21:4672. [PMID: 34300412 PMCID: PMC8309655 DOI: 10.3390/s21144672] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/28/2021] [Accepted: 07/06/2021] [Indexed: 11/17/2022]
Abstract
The detection of glucose is crucial in the management of diabetes and other medical conditions but also crucial in a wide range of industries such as food and beverages. The development of glucose sensors in the past century has allowed diabetic patients to effectively manage their disease and has saved lives. First-generation glucose sensors have considerable limitations in sensitivity and selectivity which has spurred the development of more advanced approaches for both the medical and industrial sectors. The wide range of application areas has resulted in a range of materials and fabrication techniques to produce novel glucose sensors that have higher sensitivity and selectivity, lower cost, and are simpler to use. A major focus has been on the development of enzymatic electrochemical sensors, typically using glucose oxidase. However, non-enzymatic approaches using direct electrochemistry of glucose on noble metals are now a viable approach in glucose biosensor design. This review discusses the mechanisms of electrochemical glucose sensing with a focus on the different generations of enzymatic-based sensors, their recent advances, and provides an overview of the next generation of non-enzymatic sensors. Advancements in manufacturing techniques and materials are key in propelling the field of glucose sensing, however, significant limitations remain which are highlighted in this review and requires addressing to obtain a more stable, sensitive, selective, cost efficient, and real-time glucose sensor.
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Affiliation(s)
- Mohamed H. Hassan
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK; (M.H.H.); (C.V.)
| | - Cian Vyas
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK; (M.H.H.); (C.V.)
| | - Bruce Grieve
- Department of Electrical & Electronic Engineering, University of Manchester, Manchester M13 9PL, UK;
| | - Paulo Bartolo
- Department of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL, UK; (M.H.H.); (C.V.)
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Abstract
In recent years, the field of nanoporous metals has undergone accelerated developments as these materials possess high specific surface areas, well-defined pore sizes, functional sites, and a wide range of functional properties. Nanoporous gold (NPG) is, surely, the most attractive system in the class of nanoporous metals: it combines several desired characteristics as occurrence of surface plasmon resonances, enormous surface area, electrochemical activity, biocompatibility, in addition to feasibility in preparation. All these properties concur in the exploitatiton of NPG as an efficient and versatile sensong platform. In this regard, NPG-based sensors have shown exceptional sensitivity and selectivity to a wide range of analytes ranging from molecules to biomolecules (and until the single molecule detection) and the enormous surface/volume ratio was shown to be crucial in determining these performances. Thanks to these characteristics, NPG-based sensors are finding applications in medical, biological, and safety fields so as in medical diagnostics and monitoring processes. So, a rapidly growing literature is currently investigating the properties of NPG systems toward the detection of a multitude of classes of analytes highlighting strengths and limits. Due to the extension, complexity, and importance of this research field, in the present review we attempt, starting from the discussion of specific cases, to focus our attention on the basic properties of NPG in connection to the main sensing applications, i.e., surface enhanced Raman spectroscopy-based and electrochemical-based sensing. Owing to the nano-sized pore channels and Au ligaments, which are much smaller than the wavelength of visible light (400–700 nm), surface plasmon resonances of NPG can be effectively excited by visible light and presents unique features compared with other nanostructured metals, such as nanoparticles, nanorods, and nanowires. This characteristics leads to optical sensors exploiting NPG through unique surface plasmon resonance properties that can be monitored by UV-Vis, Raman, or fluorescence spectroscopy. On the other hand, the catalytic properties of NPG are exploited electrochemical sensors are on the electrical signal produced by a specific analyte adsorbed of the NPG surface. In this regard, the enourmous NPG surface area is crucial in determining the sensitivity enhancement. Due to the extension, complexity, and importance of the NPG-based sensing field, in the present review we attempt, starting from the discussion of specific cases, to focus our attention on the basic properties of NPG in connection to the main sensing applications, i.e., surface enhanced Raman spectroscopy-based and electrochemical-based sensing. Starting from the discussion of the basic morphological/structural characteristics of NPG as obtained during the fabrication step and post-fabrication processes, the review aims to a comprehensive schematization of the main classes of sensing applications highlighting the basic involved physico-chemical properties and mechanisms. In each discussed specific example, the main involved parameters and processes governing the sensing mechanism are elucidated. In this way, the review aims at establishing a general framework connecting the processes parameters to the characteristics (pore size, etc.) of the NPG. Some examples are discussed concerning surface plasmon enhanced Uv-Vis, Raman, fluorescence spectroscopy in order to realize efficient NPG-based optical sesnors: in this regard, the underlaying connections between NPG structural/morphological properties and the optical response and, hence, the optical-based sensing performances are described and analyzed. Some other examples are discussed concerning the exploitation of the electrochemical characteristics of NPG for ultra-high sensitivity detection of analytes: in this regard, the key parameters determing the NPG activity and selectivity selectivity toward a variety of reactants are discussed, as high surface-to-volume ratio and the low coordination of surface atoms. In addition to the use of standard NPG films and leafs as sensing platforms, also the role of hybrid NPG-based nanocomposites and of nanoporous Au nanostructures is discussed due to the additional increase of the electrocatalytic acticvity and of exposed surface area resulting in the possible further sensitivity increase.
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Recent advances in electrochemical non-enzymatic glucose sensors - A review. Anal Chim Acta 2018; 1033:1-34. [PMID: 30172314 DOI: 10.1016/j.aca.2018.05.051] [Citation(s) in RCA: 315] [Impact Index Per Article: 52.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/23/2018] [Accepted: 05/18/2018] [Indexed: 12/13/2022]
Abstract
This review encompasses the mechanisms of electrochemical glucose detection and recent advances in non-enzymatic glucose sensors based on a variety of materials ranging from platinum, gold, metal alloys/adatom, non-precious transition metal/metal oxides to glucose-specific organic materials. It shows that the discovery of new materials based on unique nanostructures have not only provided the detailed insight into non-enzymatic glucose oxidation, but also demonstrated the possibility of direct detection in whole blood or interstitial fluids. We critically evaluate various aspects of non-enzymatic electrochemical glucose sensors in terms of significance as well as performance. Beyond laboratory tests, the prospect of commercialization of non-enzymatic glucose sensors is discussed.
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Graf M, Haensch M, Carstens J, Wittstock G, Weissmüller J. Electrocatalytic methanol oxidation with nanoporous gold: microstructure and selectivity. NANOSCALE 2017; 9:17839-17848. [PMID: 29116276 DOI: 10.1039/c7nr05124g] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The properties of Nanoporous Gold (NPG) obtained by the selective dissolution of Ag from an Au-Ag alloy can be tuned by the details of its fabrication, and specifically the residual Ag content is correlated to the ligament size of the material. We link this correlation to methanol electro-oxidation. Specifically, two different NPG types (obtained by potentiostatic dealloying) are compared with one obtained by free corrosion. They show remarkable differences in activity. Quantitative product analysis reveals that NPG shows nearly selective oxidation of CH3OH to HCOO- when NPG is used as an active electrode in contrast to planar Au. This trend can further be enhanced when applying finer nanoporous structures that are linked to a higher Ag content. X-ray photoelectron spectroscopy (XPS) reveals changes in the nature of residual Ag from which we conclude that Ag is not a passive component in the methanol oxidation process.
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Affiliation(s)
- Matthias Graf
- Institute of Materials Physics and Technology, Hamburg University of Technology, Hamburg, Germany.
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Matharu Z, Daggumati P, Wang L, Dorofeeva TS, Li Z, Seker E. Nanoporous-Gold-Based Electrode Morphology Libraries for Investigating Structure-Property Relationships in Nucleic Acid Based Electrochemical Biosensors. ACS APPLIED MATERIALS & INTERFACES 2017; 9:12959-12966. [PMID: 28094510 DOI: 10.1021/acsami.6b15212] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Nanoporous gold (np-Au) electrode coatings significantly enhance the performance of electrochemical nucleic acid biosensors because of their three-dimensional nanoscale network, high electrical conductivity, facile surface functionalization, and biocompatibility. Contrary to planar electrodes, the np-Au electrodes also exhibit sensitive detection in the presence of common biofouling media due to their porous structure. However, the pore size of the nanomatrix plays a critical role in dictating the extent of biomolecular capture and transport. Small pores perform better in the case of target detection in complex samples by filtering out the large nonspecific proteins. On the other hand, larger pores increase the accessibility of target nucleic acids in the nanoporous structure, enhancing the detection limits of the sensor at the expense of more interference from biofouling molecules. Here, we report a microfabricated np-Au multiple electrode array that displays a range of electrode morphologies on the same chip for identifying feature sizes that reduce the nonspecific adsorption of proteins but facilitate the permeation of target DNA molecules into the pores. We demonstrate the utility of the electrode morphology library in studying DNA functionalization and target detection in complex biological media with a special emphasis on revealing ranges of electrode morphologies that mutually enhance the limit of detection and biofouling resilience. We expect this technique to assist in the development of high-performance biosensors for point-of-care diagnostics and facilitate studies on the electrode structure-property relationships in potential applications ranging from neural electrodes to catalysts.
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Affiliation(s)
- Zimple Matharu
- Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States
| | - Pallavi Daggumati
- Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States
| | - Ling Wang
- Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States
| | - Tatiana S Dorofeeva
- Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States
| | - Zidong Li
- Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States
| | - Erkin Seker
- Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States
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Siepenkoetter T, Salaj-Kosla U, Xiao X, Belochapkine S, Magner E. Nanoporous Gold Electrodes with Tuneable Pore Sizes for Bioelectrochemical Applications. ELECTROANAL 2016. [DOI: 10.1002/elan.201600249] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Till Siepenkoetter
- Department of Chemical and Environmental Sciences, Synthesis and Solid State Pharmaceutical Centre, Bernal Institute; University of Limerick; Ireland
| | - Urszula Salaj-Kosla
- Department of Chemical and Environmental Sciences, Synthesis and Solid State Pharmaceutical Centre, Bernal Institute; University of Limerick; Ireland
| | - Xinxin Xiao
- Department of Chemical and Environmental Sciences, Synthesis and Solid State Pharmaceutical Centre, Bernal Institute; University of Limerick; Ireland
| | - Serguei Belochapkine
- Department of Chemical and Environmental Sciences, Synthesis and Solid State Pharmaceutical Centre, Bernal Institute; University of Limerick; Ireland
| | - Edmond Magner
- Department of Chemical and Environmental Sciences, Synthesis and Solid State Pharmaceutical Centre, Bernal Institute; University of Limerick; Ireland
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