1
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Bera S, Fereiro JA, Saxena SK, Chryssikos D, Majhi K, Bendikov T, Sepunaru L, Ehre D, Tornow M, Pecht I, Vilan A, Sheves M, Cahen D. Near-Temperature-Independent Electron Transport Well beyond Expected Quantum Tunneling Range via Bacteriorhodopsin Multilayers. J Am Chem Soc 2023; 145. [PMID: 37933117 PMCID: PMC10655127 DOI: 10.1021/jacs.3c09120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 10/19/2023] [Accepted: 10/20/2023] [Indexed: 11/08/2023]
Abstract
A key conundrum of biomolecular electronics is efficient electron transport (ETp) through solid-state junctions up to 10 nm, often without temperature activation. Such behavior challenges known charge transport mechanisms, especially via nonconjugated molecules such as proteins. Single-step, coherent quantum-mechanical tunneling proposed for ETp across small protein, 2-3 nm wide junctions, but it is problematic for larger proteins. Here we exploit the ability of bacteriorhodopsin (bR), a well-studied, 4-5 nm long membrane protein, to assemble into well-defined single and multiple bilayers, from ∼9 to 60 nm thick, to investigate ETp limits as a function of junction width. To ensure sufficient signal/noise, we use large area (∼10-3 cm2) Au-protein-Si junctions. Photoemission spectra indicate a wide energy separation between electrode Fermi and the nearest protein-energy levels, as expected for a polymer of mostly saturated components. Junction currents decreased exponentially with increasing junction width, with uniquely low length-decay constants (0.05-0.5 nm-1). Remarkably, even for the widest junctions, currents are nearly temperature-independent, completely so below 160 K. While, among other things, the lack of temperature-dependence excludes, hopping as a plausible mechanism, coherent quantum-mechanical tunneling over 60 nm is physically implausible. The results may be understood if ETp is limited by injection into one of the contacts, followed by more efficient charge propagation across the protein. Still, the electrostatics of the protein films further limit the number of charge carriers injected into the protein film. How electron transport across dozens of nanometers of protein layers is more efficient than injection defines a riddle, requiring further study.
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Affiliation(s)
- Sudipta Bera
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Jerry A. Fereiro
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
- School
of Chemistry, Indian Institute of Science
Education and Research, Thiruvananthapuram 695551, Kerala, India
| | - Shailendra K. Saxena
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
- Department
of Physics and Nanotechnology, College of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur, Chennai 603203, Tamil
Nadu, India
| | - Domenikos Chryssikos
- Molecular
Electronics, Technical University of Munich, 85748 Garching, Germany
- Fraunhofer
Institute for Electronic Microsystems and Solid State Technologies
(EMFT), 80686 München, Germany
| | - Koushik Majhi
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Tatyana Bendikov
- Department
of Chemical Research Support, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Lior Sepunaru
- Department
of Chemistry and Biochemistry, University
of California, Santa
Barbara, California 93106, United States
| | - David Ehre
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Marc Tornow
- Molecular
Electronics, Technical University of Munich, 85748 Garching, Germany
- Fraunhofer
Institute for Electronic Microsystems and Solid State Technologies
(EMFT), 80686 München, Germany
| | - Israel Pecht
- Department
of Immunology and Regenerative Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Ayelet Vilan
- Department
of Chemical and Biological Physics Weizmann
Institute of Science, Rehovot 7610001, Israel
| | - Mordechai Sheves
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - David Cahen
- Department
of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel
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2
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Jiang T, Zeng BF, Zhang B, Tang L. Single-molecular protein-based bioelectronics via electronic transport: fundamentals, devices and applications. Chem Soc Rev 2023; 52:5968-6002. [PMID: 37498342 DOI: 10.1039/d2cs00519k] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
Abstract
Biomolecular electronics is a rapidly growing multidisciplinary field that combines biology, nanoscience, and engineering to bridge the two important fields of life sciences and molecular electronics. Proteins are remarkable for their ability to recognize molecules and transport electrons, making the integration of proteins into electronic devices a long sought-after goal and leading to the emergence of the field of protein-based bioelectronics, also known as proteotronics. This field seeks to design and create new biomolecular electronic platforms that allow for the understanding and manipulation of protein-mediated electronic charge transport and related functional applications. In recent decades, there have been numerous reports on protein-based bioelectronics using a variety of nano-gapped electrical devices and techniques at the single molecular level, which are not achievable with conventional ensemble approaches. This review focuses on recent advances in physical electron transport mechanisms, device fabrication methodologies, and various applications in protein-based bioelectronics. We discuss the most recent progress of the single or few protein-bridged electrical junction fabrication strategies, summarise the work on fundamental and functional applications of protein bioelectronics that enable high and dynamic electron transport, and highlight future perspectives and challenges that still need to be addressed. We believe that this specific review will stimulate the interdisciplinary research of topics related to protein-related bioelectronics, and open up new possibilities for single-molecule biophysics and biomedicine.
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Affiliation(s)
- Tao Jiang
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Biao-Feng Zeng
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Bintian Zhang
- Shenzhen Key Laboratory of Precision Measurement and Early Warning Technology for Urban Environmental Health Risks, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Longhua Tang
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
- Institute of Quantum Sensing, Interdisciplinary Centre for Quantum Information, Zhejiang University, Hangzhou 310027, China
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3
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Charge Transport across Proteins inside Proteins: Tunneling across Encapsulin Protein Cages and the Effect of Cargo Proteins. Biomolecules 2023; 13:biom13010174. [PMID: 36671559 PMCID: PMC9855946 DOI: 10.3390/biom13010174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/05/2023] [Accepted: 01/10/2023] [Indexed: 01/18/2023] Open
Abstract
Charge transport across proteins can be surprisingly efficient over long distances-so-called long-range tunneling-but it is still unclear as to why and under which conditions (e.g., presence of co-factors, type of cargo) the long-range tunneling regime can be accessed. This paper describes molecular tunneling junctions based on an encapsulin (Enc), which is a large protein cage with a diameter of 24 nm that can be loaded with various types of (small) proteins, also referred to as "cargo". We demonstrate with dynamic light scattering, transmission electron microscopy, and atomic force microscopy that Enc, with and without cargo, can be made stable in solution and immobilized on metal electrodes without aggregation. We investigated the electronic properties of Enc in EGaIn-based tunnel junctions (EGaIn = eutectic alloy of Ga and In that is widely used to contact (bio)molecular monolayers) by measuring the current density for a large range of applied bias of ±2.5 V. The encapsulated cargo has an important effect on the electrical properties of the junctions. The measured current densities are higher for junctions with Enc loaded with redox-active cargo (ferritin-like protein) than those junctions without cargo or redox-inactive cargo (green fluorescent protein). These findings open the door to charge transport studies across complex biomolecular hierarchical structures.
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4
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Gupta NK, Okamoto N, Karuppannan SK, Pasula RR, Ziyu Z, Qi DC, Lim S, Nakamura M, Nijhuis CA. The Role of Structural Order in the Mechanism of Charge Transport across Tunnel Junctions with Various Iron-Storing Proteins. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2203338. [PMID: 36103613 DOI: 10.1002/smll.202203338] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/19/2022] [Indexed: 06/15/2023]
Abstract
In biomolecular electronics, the role of structural order in charge transport (CT) is poorly understood. It has been reported that the metal oxide cores of protein cages (e.g., iron oxide and ferrihydrite nanoparticles (NPs) present in ferritin and E2-LFtn, which is E2 protein engineered with an iron-binding sequence) play an important role in the mechanism of CT. At the same time, the NP core also plays a major role in the structural integrity of the proteins. This paper describes the role of structural order in CT across tunnel junctions by comparing three iron-storing proteins. They are (1) DNA binding protein from starved cells (Dps, diameter (∅) = 9 nm); (2) engineered archaeal ferritin (AfFtn-AA, ∅ = 12 nm); and (3) engineered E2 of pyruvate dehydrogenase enzyme complex (E2-LFtn, ∅ = 25 nm). Both holo-Dps and apo-Dps proteins undergo CT by coherent tunneling because their globular architecture and relative structural stability provide a coherent conduction pathway. In contrast, apo-AfFtn-AA forms a disordered structure across which charges have to tunnel incoherently, but holo-AfFtn-AA retains its globular structure and supports coherent tunneling. The large E2-LFtn always forms disordered structures across which charges incoherently tunnel regardless of the presence of the NP core. These findings highlight the importance of structural order in the mechanism of CT across biomolecular tunnel junctions.
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Affiliation(s)
- Nipun Kumar Gupta
- Department of Chemistry, National University of Singapore, 3 Science Drive, Singapore, 117543, Singapore
- Centre for Advanced 2D Materials, National University of Singapore, 6 Science Drive 2, Singapore, 117546, Singapore
| | - Naofumi Okamoto
- Division of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Senthil Kumar Karuppannan
- Department of Chemistry, National University of Singapore, 3 Science Drive, Singapore, 117543, Singapore
- National Quantum Fabless Foundry (NQFF), Institute of Materials Research and Engineering, 2 Fusionopolis Way, Innovis Building, Singapore, 138634, Singapore
| | - Rupali Reddy Pasula
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 70 Nanyang Drive, Singapore, 637457, Singapore
| | - Zhang Ziyu
- Department of Chemistry, National University of Singapore, 3 Science Drive, Singapore, 117543, Singapore
| | - Dong-Chen Qi
- Centre for Materials Science, School of Chemistry and Physics, Queensland University of Technology, Brisbane, Queensland, 4001, Australia
| | - Sierin Lim
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 70 Nanyang Drive, Singapore, 637457, Singapore
- Institute for Digital Molecular Analytics and Science, Nanyang Technological University, 59 Nanyang Drive, Experimental Medicine Building, Singapore, 636921, Singapore
| | - Masakazu Nakamura
- Division of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Christian A Nijhuis
- Department of Chemistry, National University of Singapore, 3 Science Drive, Singapore, 117543, Singapore
- Centre for Advanced 2D Materials, National University of Singapore, 6 Science Drive 2, Singapore, 117546, Singapore
- Department of Molecules and Materials, MESA+ Institute for Nanotechnology, and Center for Brain-Inspired Nano Systems (BRAINS), Faculty of Science and Technology, University of Twente, P.O. Box 217, Enschede, 7500 AE, The Netherlands
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5
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Tang L, Yi L, Jiang T, Ren R, Paulose Nadappuram B, Zhang B, Wu J, Liu X, Lindsay S, Edel JB, Ivanov AP. Measuring conductance switching in single proteins using quantum tunneling. SCIENCE ADVANCES 2022; 8:eabm8149. [PMID: 35584212 PMCID: PMC9116604 DOI: 10.1126/sciadv.abm8149] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Interpreting the electrical signatures of single proteins in electronic junctions has facilitated a better understanding of the intrinsic properties of proteins that are fundamental to chemical and biological processes. Often, this information is not accessible using ensemble and even single-molecule approaches. In addition, the fabrication of nanoscale single-protein junctions remains challenging as they often require sophisticated methods. We report on the fabrication of tunneling probes, direct measurement, and active control (switching) of single-protein conductance with an external field in solution. The probes allowed us to bridge a single streptavidin molecule to two independently addressable, biotin-terminated electrodes and measure single-protein tunneling response over long periods. We show that charge transport through the protein has multiple conductive pathways that depend on the magnitude of the applied bias. These findings open the door for the reliable fabrication of protein-based junctions and can enable their use in future protein-embedded bioelectronics applications.
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Affiliation(s)
- Longhua Tang
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, International Research Center for Advanced Photonics, Zhejiang University, Hangzhou 310027, China
- Innovation Institute for Artificial Intelligence in Medicine, Zhejiang-California International NanoSystems Institute, Zhejiang University, Hangzhou 310000, China
- Corresponding author. (L.T.); (A.P.I.); (J.B.E.)
| | - Long Yi
- Department of Chemistry, Molecular Science Research Hub, Imperial College London, White City Campus, 82 Wood Lane, London W12 0BZ, UK
| | - Tao Jiang
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, International Research Center for Advanced Photonics, Zhejiang University, Hangzhou 310027, China
| | - Ren Ren
- Department of Chemistry, Molecular Science Research Hub, Imperial College London, White City Campus, 82 Wood Lane, London W12 0BZ, UK
| | - Binoy Paulose Nadappuram
- Department of Chemistry, Molecular Science Research Hub, Imperial College London, White City Campus, 82 Wood Lane, London W12 0BZ, UK
- Department of Pure and Applied Chemistry, University of Strathclyde, Technology and Innovation Centre, 99 George Street, Glasgow G1 1RD, UK
| | - Bintian Zhang
- Biodesign Institute; School of Life Sciences; Department of Physics; School of Molecular Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Jian Wu
- Innovation Institute for Artificial Intelligence in Medicine, Zhejiang-California International NanoSystems Institute, Zhejiang University, Hangzhou 310000, China
| | - Xu Liu
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, International Research Center for Advanced Photonics, Zhejiang University, Hangzhou 310027, China
| | - Stuart Lindsay
- Biodesign Institute; School of Life Sciences; Department of Physics; School of Molecular Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Joshua B. Edel
- Department of Chemistry, Molecular Science Research Hub, Imperial College London, White City Campus, 82 Wood Lane, London W12 0BZ, UK
- Corresponding author. (L.T.); (A.P.I.); (J.B.E.)
| | - Aleksandar P. Ivanov
- Department of Chemistry, Molecular Science Research Hub, Imperial College London, White City Campus, 82 Wood Lane, London W12 0BZ, UK
- Corresponding author. (L.T.); (A.P.I.); (J.B.E.)
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6
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Zhang B, Ryan E, Wang X, Song W, Lindsay S. Electronic Transport in Molecular Wires of Precisely Controlled Length Built from Modular Proteins. ACS NANO 2022; 16:1671-1680. [PMID: 35029115 PMCID: PMC9279515 DOI: 10.1021/acsnano.1c10830] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
DNA molecular wires have been studied extensively because of the ease with which molecules of controlled length and composition can be synthesized. The same has not been true for proteins. Here, we have synthesized and studied a series of consensus tetratricopeptide repeat (CTPR) proteins, spanning 4 to 20 nm in length, in increments of 4 nm. For lengths in excess of 6 nm, their conductance exceeds that of the canonical molecular wire, oligo(phenylene-ethylenene), because of the more gradual decay of conductance with length in the protein. We show that, while the conductance decay fits an exponential (characteristic of quantum tunneling) and not a linear increase of resistance with length (characteristic of hopping transport), it is also accounted for by a square-law dependence on length (characteristic of weakly driven hopping). Measurements of the energy dependence of the decay length rule out the quantum tunneling case. A resonance in the carrier injection energy shows that allowed states in the protein align with the Fermi energy of the electrodes. Both the energy of these states and the long-range of hopping suggest that the reorganization induced by hole formation is greatly reduced inside the protein. We outline a model for calculating the molecular-electronic properties of proteins.
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Affiliation(s)
- Bintian Zhang
- Biodesign Institute, Arizona State University, Tempe, AZ 85281
| | - Eathen Ryan
- School of Molecular Sciences, Arizona State University, Tempe, AZ 85281
| | - Xu Wang
- School of Molecular Sciences, Arizona State University, Tempe, AZ 85281
| | - Weisi Song
- Biodesign Institute, Arizona State University, Tempe, AZ 85281
| | - Stuart Lindsay
- Biodesign Institute, Arizona State University, Tempe, AZ 85281
- School of Molecular Sciences, Arizona State University, Tempe, AZ 85281
- Department of Physics, Arizona State University, Tempe, AZ 85281
- Corresponding Author: Stuart Lindsay: Phone 480 205 6432
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7
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Fereiro JA, Pecht I, Sheves M, Cahen D. Inelastic Electron Tunneling Spectroscopic Analysis of Bias-Induced Structural Changes in a Solid-State Protein Junction. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2008218. [PMID: 33783130 DOI: 10.1002/smll.202008218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/10/2021] [Indexed: 05/25/2023]
Abstract
A central issue in protein electronics is how far the structural stability of the protein is preserved under the very high electrical field that it will experience once a bias voltage is applied. This question is studied on the redox protein Azurin in the solid-state Au/protein/Au junction by monitoring protein vibrations during current transport under applied bias, up to ≈1 GV m-1 , by electrical detection of inelastic electron transport effects. Characteristic vibrational modes, such as CH stretching, amide (NH) bending, and AuS (of the bonds that connect the protein to an Au electrode), are not found to change noticeably up to 1.0 V. At >1.0 V, the NH bending and CH stretching inelastic features have disappeared, while the AuS features persist till ≈2 V, i.e., the proteins remain Au bound. Three possible causes for the disappearance of the NH and CH inelastic features at high bias, namely, i) resonance transport, ii) metallic filament formation, and iii) bond rupture leading to structural changes in the protein are proposed and tested. The results support the last option and indicate that spectrally resolved inelastic features can serve to monitor in operando structural stability of biological macromolecules while they serve as electronic current conduit.
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Affiliation(s)
- Jerry A Fereiro
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Israel Pecht
- Department of Immunology, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Mordechai Sheves
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - David Cahen
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 7610001, Israel
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8
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The Role of Metal Ions in the Electron Transport through Azurin-Based Junctions. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11093732] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
We studied the coherent electron transport through metal–protein–metal junctions based on a blue copper azurin, in which the copper ion was replaced by three different metal ions (Co, Ni and Zn). Our results show that neither the protein structure nor the transmission at the Fermi level change significantly upon metal replacement. The discrepancy with previous experimental observations suggests that the transport mechanism taking place in these types of junctions is probably not fully coherent.
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9
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Mukhopadhyay S, Karuppannan SK, Guo C, Fereiro JA, Bergren A, Mukundan V, Qiu X, Castañeda Ocampo OE, Chen X, Chiechi RC, McCreery R, Pecht I, Sheves M, Pasula RR, Lim S, Nijhuis CA, Vilan A, Cahen D. Solid-State Protein Junctions: Cross- Laboratory Study Shows Preservation of Mechanism at Varying Electronic Coupling. iScience 2020; 23:101099. [PMID: 32438319 PMCID: PMC7235645 DOI: 10.1016/j.isci.2020.101099] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 03/01/2020] [Accepted: 04/20/2020] [Indexed: 12/14/2022] Open
Abstract
Successful integration of proteins in solid-state electronics requires contacting them in a non-invasive fashion, with a solid conducting surface for immobilization as one such contact. The contacts can affect and even dominate the measured electronic transport. Often substrates, substrate treatments, protein immobilization, and device geometries differ between laboratories. Thus the question arises how far results from different laboratories and platforms are comparable and how to distinguish genuine protein electronic transport properties from platform-induced ones. We report a systematic comparison of electronic transport measurements between different laboratories, using all commonly used large-area schemes to contact a set of three proteins of largely different types. Altogether we study eight different combinations of molecular junction configurations, designed so that Ageoof junctions varies from 105 to 10-3 μm2. Although for the same protein, measured with similar device geometry, results compare reasonably well, there are significant differences in current densities (an intensive variable) between different device geometries. Likely, these originate in the critical contact-protein coupling (∼contact resistance), in addition to the actual number of proteins involved, because the effective junction contact area depends on the nanometric roughness of the electrodes and at times, even the proteins may increase this roughness. On the positive side, our results show that understanding what controls the coupling can make the coupling a design knob. In terms of extensive variables, such as temperature, our comparison unanimously shows the transport to be independent of temperature for all studied configurations and proteins. Our study places coupling and lack of temperature activation as key aspects to be considered in both modeling and practice of protein electronic transport experiments.
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Affiliation(s)
- Sabyasachi Mukhopadhyay
- Weizmann Institute of Science, Rehovot 76100, Israel
- Department of Physics, SRM University – AP, Amaravati, Andhra Pradesh 522502, India
| | - Senthil Kumar Karuppannan
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Cunlan Guo
- Weizmann Institute of Science, Rehovot 76100, Israel
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, P. R. China
| | | | - Adam Bergren
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton AB T6G 2G2, Canada
| | - Vineetha Mukundan
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton AB T6G 2G2, Canada
| | - Xinkai Qiu
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands
| | - Olga E. Castañeda Ocampo
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands
| | - Xiaoping Chen
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
| | - Ryan C. Chiechi
- Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands
| | - Richard McCreery
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Dr., Edmonton AB T6G 2G2, Canada
| | - Israel Pecht
- Weizmann Institute of Science, Rehovot 76100, Israel
| | | | - Rupali Reddy Pasula
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 70 Nanyang Drive, Singapore 637457, Singapore
| | - Sierin Lim
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 70 Nanyang Drive, Singapore 637457, Singapore
| | - Christian A. Nijhuis
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore
- Centre for Advanced 2D Materials, National University of Singapore, 6 Science Drive 2, Singapore 117546, Singapore
| | - Ayelet Vilan
- Weizmann Institute of Science, Rehovot 76100, Israel
| | - David Cahen
- Weizmann Institute of Science, Rehovot 76100, Israel
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10
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Zhuang X, Zhang A, Qiu S, Tang C, Zhao S, Li H, Zhang Y, Wang Y, Wang B, Fang B, Hong W. Coenzyme Coupling Boosts Charge Transport through Single Bioactive Enzyme Junctions. iScience 2020; 23:101001. [PMID: 32259671 PMCID: PMC7136626 DOI: 10.1016/j.isci.2020.101001] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 03/09/2020] [Accepted: 03/18/2020] [Indexed: 12/15/2022] Open
Abstract
Oxidation of formate to CO2 is catalyzed via the donation of electrons from formate dehydrogenase (FDH) to nicotinamide adenine dinucleotide (NAD+), and thus the charge transport characteristics of FDH become essential but remain unexplored. Here, we investigated the charge transport through single-enzyme junctions of FDH using the scanning tunneling microscope break junction technique (STM-BJ). We found that the coupling of NAD+ with FDH boosts the charge transport by ∼2,100%, and the single-enzyme conductance highly correlates with the enzyme activity. The combined flicker noise analysis demonstrated the switching of the coenzyme-mediated charge transport pathway and supported by the significantly reduced HOMO-LUMO gap from calculations. Site-specific mutagenesis analysis demonstrated that FDH-NAD+ stably combined own higher bioactivity and boosts charge transport, and the coupling has been optimized via the natural selection. Our work provides evidence of hydrogen bond coupling in bioactivity but also bridges the charge transport through single-enzyme junctions and enzyme activities. Binding of NAD+ with FDH boosts the charge transport by more than 2,100% Single-enzyme conductance highly correlates with the enzyme activity Hydrogen bond bridges the charge transport and enzyme activities Experiments combined with calculations probe switching of charge transport pathway
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Affiliation(s)
- Xiaoyan Zhuang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China; The Key Laboratory for Chemical Biology of Fujian Province, Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen 361005, China
| | - Aihui Zhang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China; The Key Laboratory for Chemical Biology of Fujian Province, Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen 361005, China
| | - Siyao Qiu
- Science & Technology Innovation Institute, Dongguan University of Technology, Dongguan 523018, China
| | - Chun Tang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Shiqiang Zhao
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Hongchun Li
- Research Center for Computer-Aided Drug Discovery, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Yonghui Zhang
- College of Food and Biology Engineering, Jimei University, Xiamen 361005, China
| | - Yali Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China; The Key Laboratory for Chemical Biology of Fujian Province, Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen 361005, China
| | - Binju Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Baishan Fang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China; The Key Laboratory for Chemical Biology of Fujian Province, Key Lab for Synthetic Biotechnology of Xiamen City, Xiamen University, Xiamen 361005, China.
| | - Wenjing Hong
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
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11
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Kayser B, Fereiro JA, Bhattacharyya R, Cohen SR, Vilan A, Pecht I, Sheves M, Cahen D. Solid-State Electron Transport via the Protein Azurin is Temperature-Independent Down to 4 K. J Phys Chem Lett 2020; 11:144-151. [PMID: 31821001 DOI: 10.1021/acs.jpclett.9b03120] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Solid-state electronic transport (ETp) via the electron-transfer copper protein azurin (Az) was measured in Au/Az/Au junction configurations down to 4 K, the lowest temperature for solid-state protein-based junctions. Not only does lowering the temperature help when observing fine features of electronic transport, but it also limits possible electron transport mechanisms. Practically, wire-bonded devices-on-chip, carrying Az-based microscopic junctions, were measured in liquid He, minimizing temperature gradients across the samples. Much smaller junctions, in conducting-probe atomic force microscopy measurements, served, between room temperature and the protein's denaturation temperature (∼323 K), to check that conductance behavior is independent of device configuration or contact nature and thus is a property of the protein itself. Temperature-independent currents were observed from ∼320 to 4 K. The experimental results were fitted to a single-level Landauer model to extract effective energy barrier and electrode-molecule coupling strength values and to compare data sets. Our results strongly support that quantum tunneling, rather than hopping, dominates ETp via Az.
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Affiliation(s)
- Ben Kayser
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Jerry A Fereiro
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Rajarshi Bhattacharyya
- Braun Center for Submicron Research, Department of Condensed Matter Physics , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Sidney R Cohen
- Department of Chemical Research Support , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Ayelet Vilan
- Department of Chemical and Biological Physics , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Israel Pecht
- Department of Immunology , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - Mordechai Sheves
- Department of Organic Chemistry , Weizmann Institute of Science , Rehovot 76100 , Israel
| | - David Cahen
- Department of Materials and Interfaces , Weizmann Institute of Science , Rehovot 76100 , Israel
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12
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Song X, Fu Q, Bu Y. Nonlinear Migration Dynamics of Excess Electrons along Linear Oligopeptides Controlled by an Applied Electric Field. Chemphyschem 2019; 20:1497-1507. [PMID: 30912277 DOI: 10.1002/cphc.201900149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 03/16/2019] [Indexed: 11/06/2022]
Abstract
Migration of an excess electron along linear oligopeptides governed by the external electric field (Eex ) which is against the inner dipole electric field is theoretically investigated, including the effects of Eex on the structural and electronic properties of electron migration. Two structural properties including electron-binding ability and the dipole moment of linear oligopeptides are sensitive to the Eex values and can be largely modulated by Eex due to the competition of Eex and the inner electric field and electron transfer caused by Eex . In the case of low Eex values, two structural properties decrease slightly, while for high Eex values, the electron-binding ability continually increases strongly, with dipole moments firstly increasing significantly and then increasing more slowly at higher Eex . Additionally, linear oligopeptides of different chain lengths influence the modulation extent of Eex and the longer the chain length is, the more sensitive modulation of Eex is. In addition, electronic properties represented by electron spin densities and singly occupied molecular orbital distributions vary with Eex intensities, leading to an unusual electron migration behavior. As Eex increases, an excess electron transfers from the N-terminus to the C-terminus and jumps over a neighboring dipole unit of two termini to other units, respectively, instead of transferring by means of a one-by-one dipole unit hopping mechanism. These findings not only promote a deeper understanding of the connection between Eex and structural and electronic properties of electron transfer behavior in peptides, but also provide a new insight into the modulation of electron migration along the oligopeptides.
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Affiliation(s)
- Xiufang Song
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, People's Republic of China
| | - Qiang Fu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, People's Republic of China
| | - Yuxiang Bu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, People's Republic of China.,School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, People's Republic of China
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13
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Song X, Zhang F, Bu Y. Dynamic relaying properties of a β-turn peptide in long-range electron transfer. J Comput Chem 2019; 40:988-996. [PMID: 30451309 DOI: 10.1002/jcc.25541] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 06/30/2018] [Accepted: 07/03/2018] [Indexed: 11/05/2022]
Abstract
The relay stations play a significant role in long-range charge hopping transfer in proteins. Although studies have clarified that many more protein structural motifs can function as relays in charge hopping transfers by acting as intermediate charge carriers, the relaying properties are still poorly understood. In this work, taking a β-turn oligopeptide as an example, we report a dynamic character of a relay with tunable relaying properties using the density functional theory calculations. Our main finding is that a β-turn peptide can serve as an effective electron relay in facilitating long-range electron migration and its relay properties is vibration-tunable. The vibration-induced structural transient distortions remarkably affect the lowest occupied molecular orbital (LUMO) energy, vertical electron affinity and electron-binding mode of the β-turn oligopeptide and the singly occupied molecular orbital (SOMO) energy of the corresponding electron adduct and thus the relaying properties. Different vibration modes lead to different structural distortions and thus have different effects on the relaying properties and ability of the β-turn peptide. For the relaying properties, there approximately is a linear negative correlation of electron affinity with the LUMO energy of the β-turn or the SOMO energy of its electron adduct. Besides, such relaying properties also vary in the vibration evolution process, and the electron-binding modes may be tunable. As an important addition to the known static charge relaying properties occurring in various protein structural motifs, this work reports the dynamic electron-relaying characteristics of a β-turn oligopeptide with variable relaying properties governed by molecular vibrations which can be applied to different proteins in mediating long-range charge transfers. Clearly, this work reveals molecular vibration effects on the electron relaying properties of protein structural motifs and provides new insights into the dynamics of long-range charge transfers in proteins. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Xiufang Song
- School of Chemistry &Chemical Engineering, Institute of Theoretical Chemistry, Shandong University, Jinan 250100, People's Republic of China
| | - Fengying Zhang
- School of Chemistry &Chemical Engineering, Institute of Theoretical Chemistry, Shandong University, Jinan 250100, People's Republic of China
| | - Yuxiang Bu
- School of Chemistry &Chemical Engineering, Institute of Theoretical Chemistry, Shandong University, Jinan 250100, People's Republic of China
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14
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Kayser B, Fereiro JA, Guo C, Cohen SR, Sheves M, Pecht I, Cahen D. Transistor configuration yields energy level control in protein-based junctions. NANOSCALE 2018; 10:21712-21720. [PMID: 30431054 DOI: 10.1039/c8nr06627b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The incorporation of proteins as functional components in electronic junctions has received much interest recently due to their diverse bio-chemical and physical properties. However, information regarding the energies of the frontier orbitals involved in their electron transport (ETp) has remained elusive. Here we employ a new method to quantitatively determine the energy position of the molecular orbital, nearest to the Fermi level (EF) of the electrode, in the electron transfer protein Azurin. The importance of the Cu(ii) redox center of Azurin is demonstrated by measuring gate-controlled conductance switching which is absent if Azurin's copper ions are removed. Comparing different electrode materials, a higher conductance and a lower gate-induced current onset is observed for the material with smaller work function, indicating that ETp via Azurin is LUMO-mediated. We use the difference in work function to calibrate the difference in gate-induced current onset for the two electrode materials, to a specific energy level shift and find that ETp via Azurin is near resonance. Our results provide a basis for mapping and studying the role of energy level positions in (bio)molecular junctions.
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Affiliation(s)
- Ben Kayser
- Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 76100, Israel.
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15
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Qiu X, Castañeda Ocampo O, de Vries HW, van Putten M, Loznik M, Herrmann A, Chiechi RC. Self-Regenerating Soft Biophotovoltaic Devices. ACS APPLIED MATERIALS & INTERFACES 2018; 10:37625-37633. [PMID: 30295451 PMCID: PMC6328238 DOI: 10.1021/acsami.8b11115] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
This paper describes the fabrication of soft, stretchable biophotovoltaic devices that generate photocurrent from photosystem I (PSI) complexes that are self-assembled onto Au electrodes with a preferred orientation. Charge is collected by the direct injection of electrons into the Au electrode and the transport of holes through a redox couple to liquid eutectic gallium-indium (EGaIn) electrodes that are confined to microfluidic pseudochannels by arrays of posts. The pseudochannels are defined in a single fabrication step that leverages the non-Newtonian rheology of EGaIn. This strategy is extended to the fabrication of reticulated electrodes that are inherently stretchable. A simple shadow evaporation technique is used to increase the surface area of the Au electrodes by a factor of approximately 106 compared to planar electrodes. The power conversion efficiency of the biophotovoltaic devices decreases over time, presumably as the PSI complexes denature and/or detach from the Au electrodes. However, by circulating a solution of active PSI complexes the devices self-regenerate by mass action/self-assembly. These devices leverage simple fabrication techniques to produce complex function and prove that photovoltaic devices comprising PSI can retain the ability to regenerate, one of the most important functions of photosynthetic organisms.
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Affiliation(s)
- Xinkai Qiu
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Olga Castañeda Ocampo
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Hendrik W. de Vries
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Maikel van Putten
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Mark Loznik
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Andreas Herrmann
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Ryan C. Chiechi
- Zernike
Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Stratingh
Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- E-mail:
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16
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Tunneling explains efficient electron transport via protein junctions. Proc Natl Acad Sci U S A 2018; 115:E4577-E4583. [PMID: 29712853 DOI: 10.1073/pnas.1719867115] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Metalloproteins, proteins containing a transition metal ion cofactor, are electron transfer agents that perform key functions in cells. Inspired by this fact, electron transport across these proteins has been widely studied in solid-state settings, triggering the interest in examining potential use of proteins as building blocks in bioelectronic devices. Here, we report results of low-temperature (10 K) electron transport measurements via monolayer junctions based on the blue copper protein azurin (Az), which strongly suggest quantum tunneling of electrons as the dominant charge transport mechanism. Specifically, we show that, weakening the protein-electrode coupling by introducing a spacer, one can switch the electron transport from off-resonant to resonant tunneling. This is a consequence of reducing the electrode's perturbation of the Cu(II)-localized electronic state, a pattern that has not been observed before in protein-based junctions. Moreover, we identify vibronic features of the Cu(II) coordination sphere in transport characteristics that show directly the active role of the metal ion in resonance tunneling. Our results illustrate how quantum mechanical effects may dominate electron transport via protein-based junctions.
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17
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Bostick CD, Mukhopadhyay S, Pecht I, Sheves M, Cahen D, Lederman D. Protein bioelectronics: a review of what we do and do not know. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:026601. [PMID: 29303117 DOI: 10.1088/1361-6633/aa85f2] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We review the status of protein-based molecular electronics. First, we define and discuss fundamental concepts of electron transfer and transport in and across proteins and proposed mechanisms for these processes. We then describe the immobilization of proteins to solid-state surfaces in both nanoscale and macroscopic approaches, and highlight how different methodologies can alter protein electronic properties. Because immobilizing proteins while retaining biological activity is crucial to the successful development of bioelectronic devices, we discuss this process at length. We briefly discuss computational predictions and their connection to experimental results. We then summarize how the biological activity of immobilized proteins is beneficial for bioelectronic devices, and how conductance measurements can shed light on protein properties. Finally, we consider how the research to date could influence the development of future bioelectronic devices.
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Affiliation(s)
- Christopher D Bostick
- Department of Pharmaceutical Sciences, West Virginia University, Morgantown, WV 26506, United States of America. Institute for Genomic Medicine, Columbia University Medical Center, New York, NY 10032, United States of America
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18
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Panda SS, Katz HE, Tovar JD. Solid-state electrical applications of protein and peptide based nanomaterials. Chem Soc Rev 2018; 47:3640-3658. [DOI: 10.1039/c7cs00817a] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This review summarizes recent advancements in electrical properties and applications of natural proteins and mutated variants, synthetic oligopeptides and peptide–π conjugates.
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Affiliation(s)
- Sayak Subhra Panda
- Department of Chemistry
- Krieger School of Arts and Sciences
- Johns Hopkins University
- Baltimore
- USA
| | - Howard E. Katz
- Department of Chemistry
- Krieger School of Arts and Sciences
- Johns Hopkins University
- Baltimore
- USA
| | - John D. Tovar
- Department of Chemistry
- Krieger School of Arts and Sciences
- Johns Hopkins University
- Baltimore
- USA
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19
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Pulka-Ziach K, Sęk S. α-Helicomimetic foldamers as electron transfer mediators. NANOSCALE 2017; 9:14913-14920. [PMID: 28949361 DOI: 10.1039/c7nr05209j] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
α-Helical peptides are known as efficient mediators of electron transfer; however, their use is limited to compounds longer that 7-10 residues. To overcome this limitation, α-helicomimetic foldamers, based on the oligourea backbone with the general formula [-CH(R)-CH2-NH-CO-NH]n, were synthesized. Oligoureas are known to adopt a robust 2.5-helical conformation where only four residues are enough to form stable 1.5 helical turns. This feature makes them great models to study the charge transfer process and the dependence of the mechanism of the electron transition on the length of the mediator. Two families of different chain length (2, 4 and 6 residues) oligoureas were synthesized with a thiol group attached to the δ+ or δ- helix dipole pole. This enables the adsorption of the molecules onto the gold surface, leading to the formation of self-assembled monolayers. The helicity of compounds was confirmed in solution and in the solid state. Such systems were used to study the electron transfer process by current sensing atomic force microscopy (CS-AFM). The results showed that oligoureas may act as electron transfer mediators. Additionally, it was shown by the increasing force applied to the AFM tip that the oligourea helix is more stable than the helix formed by peptides.
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Affiliation(s)
- K Pulka-Ziach
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland.
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20
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Vilan A, Aswal D, Cahen D. Large-Area, Ensemble Molecular Electronics: Motivation and Challenges. Chem Rev 2017; 117:4248-4286. [DOI: 10.1021/acs.chemrev.6b00595] [Citation(s) in RCA: 243] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Ayelet Vilan
- Department
of Materials and Interfaces, Weizmann Institute of Science, Rehovot, Israel
| | | | - David Cahen
- Department
of Materials and Interfaces, Weizmann Institute of Science, Rehovot, Israel
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21
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Mukhopadhyay S, Gärtner W, Cahen D, Pecht I, Sheves M. Electron transport via a soluble photochromic photoreceptor. Phys Chem Chem Phys 2016; 18:25671-25675. [DOI: 10.1039/c6cp05011e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electron transport properties via a photochromic biological photoreceptor have been studied in junctions of monolayer assemblies in solid-state configurations.
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Affiliation(s)
- Sabyasachi Mukhopadhyay
- Department of Materials and Interfaces
- Weizmann Institute of Science
- Israel
- Department of Organic Chemistry
- Weizmann Institute of Science
| | - Wolfgang Gärtner
- Max Planck Institute for Chemical Energy Conversion
- 45470 Mülheim a.d. Ruhr
- Germany
| | - David Cahen
- Department of Materials and Interfaces
- Weizmann Institute of Science
- Israel
| | - Israel Pecht
- Department of Immunology
- Weizmann Institute of Science
- Israel
| | - Mordechai Sheves
- Department of Organic Chemistry
- Weizmann Institute of Science
- Israel
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