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Dong C, Carnicer-Lombarte A, Bonafè F, Huang B, Middya S, Jin A, Tao X, Han S, Bance M, Barone DG, Fraboni B, Malliaras GG. Electrochemically actuated microelectrodes for minimally invasive peripheral nerve interfaces. NATURE MATERIALS 2024; 23:969-976. [PMID: 38671159 PMCID: PMC11230894 DOI: 10.1038/s41563-024-01886-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 03/31/2024] [Indexed: 04/28/2024]
Abstract
Electrode arrays that interface with peripheral nerves are used in the diagnosis and treatment of neurological disorders; however, they require complex placement surgeries that carry a high risk of nerve injury. Here we leverage recent advances in soft robotic actuators and flexible electronics to develop highly conformable nerve cuffs that combine electrochemically driven conducting-polymer-based soft actuators with low-impedance microelectrodes. Driven with applied voltages as small as a few hundreds of millivolts, these cuffs allow active grasping or wrapping around delicate nerves. We validate this technology using in vivo rat models, showing that the cuffs form and maintain a self-closing and reliable bioelectronic interface with the sciatic nerve of rats without the use of surgical sutures or glues. This seamless integration of soft electrochemical actuators with neurotechnology offers a path towards minimally invasive intraoperative monitoring of nerve activity and high-quality bioelectronic interfaces.
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Affiliation(s)
- Chaoqun Dong
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | | | - Filippo Bonafè
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy
| | - Botian Huang
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Sagnik Middya
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Amy Jin
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Xudong Tao
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Sanggil Han
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
- Department of Nano-Bioengineering, Incheon National University, Incheon, Republic of Korea
| | - Manohar Bance
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Damiano G Barone
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Beatrice Fraboni
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy
| | - George G Malliaras
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK.
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Kim Y, Yoshida Y. A Lightweight and Low-Voltage-Operating Linear Actuator Based on the Electroactive Polymer Polypyrrole. Polymers (Basel) 2023; 15:3455. [PMID: 37631512 PMCID: PMC10459993 DOI: 10.3390/polym15163455] [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: 07/09/2023] [Revised: 08/08/2023] [Accepted: 08/10/2023] [Indexed: 08/27/2023] Open
Abstract
In recent decades, significant research efforts have been devoted to studying various types of actuators. Of particular interest are soft actuators based on electroactive polymers, which offer low operating voltage, light weight, and fast response. In this study, we demonstrate the feasibility of a soft linear actuator fabricated from polypyrrole (PPy), an electroactive polymer that is easy to synthesize, cost-effective, and biocompatible. By optimizing the polymerization conditions, the operation condition and environment, we were able to achieve improved and stable actuator performance. Furthermore, we developed a new actuator-contained component with a flexible counter electrode to build an actuator that operates in air. This approach enabled us to build small and lightweight actuators that operate in air, with a diameter of 5 mm, resembling artificial muscles. Our resulting miniaturized and integrated linear PPy-based actuators can be driven at low voltages (±1.5 V), making them suitable for use in various parts of the body. As such, this actuator holds significant potential for a wide range of applications in the fields of soft electronics, drug delivery, artificial organs, and muscles, as well as a component material for portable medical sensors and devices.
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Affiliation(s)
- Yeji Kim
- Advanced Technology Research Department, LG Japan Lab Inc., LG Yokohama Innovation Center 1-2-13, Takashima, Nishi-ku, Yokohama-shi, Kanagawa 220-0011, Japan;
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Role of Polyoxometalate Contents in Polypyrrole: Linear Actuation and Energy Storage. MATERIALS 2022; 15:ma15103619. [PMID: 35629645 PMCID: PMC9145510 DOI: 10.3390/ma15103619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 05/13/2022] [Accepted: 05/16/2022] [Indexed: 12/10/2022]
Abstract
A combination of polyoxometalates with polypyrrole is introduced in this work. Our goal was to include phosphotungstic acid (PTA) in different molar concentrations (0.005, 0.01, and 0.05 M) in the electropolymerization of pyrrole doped with dodecylbenzene sulfonate (DBS) and phosphotungstinates (PT), forming PPy/DBS-PT films. Scanning electron microscopy (SEM) revealed that the PPy/DBS-PT films became denser and more compact with increasing PTA concentrations. The incorporation of PT in PPy/DBS was analyzed using Fourier-transform infrared (FTIR) and energy dispersive X-ray (EDX) spectroscopy. The linear actuation in cyclic voltammetry and potential square wave steps in an organic electrolyte revealed increasing mixed actuation, with major expansion upon oxidation found for PPy/DBS-PT films with a PTA concentration of 0.005 M. Best results of a strain of 12.8% and stress at 0.68 MPa were obtained for PPy/DBS-PT (0.01 M). The PPy/DBS-PT films polymerized in the presence of 0.05 M of PTA and showed main expansion upon reduction, changing the actuation direction. Chronopotentiometric measurements of PPy/DBS-PT samples were conducted to determine the specific capacitance optimal for a 0.01 M PTA concentration in the range of 80 F g−1 (±0.22 A g−1).
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Polypyrrole Polyethylene Composite for Controllable Linear Actuators in Different Organic Electrolytes. MATERIALS 2022; 15:ma15020540. [PMID: 35057260 PMCID: PMC8781785 DOI: 10.3390/ma15020540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/29/2021] [Accepted: 01/05/2022] [Indexed: 11/18/2022]
Abstract
Controllable linear actuation of polypyrrole (PPy) is the envisaged goal where only one ion dominates direction (here anions) in reversible redox cycles. PPy with polyethylene oxide (PEO) doped with dodecylbenzenesulfonate forms PPy-PEO/DBS films (PPy-PEO), which are applied in propylene carbonate (PC) solvent with electrolytes such as 1-ethyl-2,3-dimethylimidazolium trifluoromethanesulfonate (EDMICF3SO3), sodium perchlorate (NaClO4) and tetrabutylammonium hexafluorophosphate (TBAPF6) and compared in their linear actuation properties with pristine PPy/DBS samples. PPy-PEO showed for all applied electrolytes that only expansion at oxidation appeared in cyclic voltammetric studies, while pristine PPy/DBS had mixed-ion actuation in all electrolytes. The electrolyte TBAPF6-PC revealed for PPy-PEO best results with 18% strain (PPy/DBS had 8.5% strain), 2 times better strain rates, 1.8 times higher electronic conductivity, 1.4 times higher charge densities and 1.5 times higher diffusion coefficients in comparison to PPy/DBS. Long-term measurements up to 1000 cycles at 0.1 Hz revealed strain over 4% for PPy-PEO linear actuators, showing that combination of PPy/DBS with PEO gives excellent material for artificial muscle-like applications envisaged for smart textiles and soft robotics. FTIR and Raman spectroscopy confirmed PEO content in PPy. Electrochemical impedance spectroscopy (EIS) of PPy samples revealed 1.3 times higher ion conductivity of PPy-PEO films in PC solvent. Scanning electron microscopy (SEM) was used to investigate morphologies of PPy samples, and EDX spectroscopy was conducted to determine ion contents of oxidized/reduced films.
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Kiefer R, Le QB, Velmurugan BK, Otero TF. Artificial muscle like behavior of polypyrrole polyethylene oxide independent of applied potential ranges. J Appl Polym Sci 2021. [DOI: 10.1002/app.52039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Rudolf Kiefer
- Conducting Polymers in Composites and Applications Research Group, Faculty of Applied Sciences Ton Duc Thang University Ho Chi Minh City Vietnam
| | - Quoc Bao Le
- Conducting Polymers in Composites and Applications Research Group, Faculty of Applied Sciences Ton Duc Thang University Ho Chi Minh City Vietnam
| | | | - Toribio F. Otero
- Centre for Electrochemistry and Intelligent Materials (CEMI) Universidad Politécnica de Cartagena Murcia Spain
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Tran CB, Zondaka Z, Le QB, Velmurugan BK, Kiefer R. Polypyrrole with Phosphor Tungsten Acid and Carbide-Derived Carbon: Change of Solvent in Electropolymerization and Linear Actuation. MATERIALS 2021; 14:ma14216302. [PMID: 34771828 PMCID: PMC8585407 DOI: 10.3390/ma14216302] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/16/2021] [Accepted: 10/19/2021] [Indexed: 11/16/2022]
Abstract
Linear actuators based on polypyrrole (PPy) are envisaged to have only one ion that triggers the actuation direction, either at oxidation (anion-driven) or at reduction (cation-driven). PPy doped with dodecylbenzenesulfonate (PPy/DBS) is the most common applied conducting polymer having cation-driven actuation in aqueous solvent and mainly anion-driven actuation in an organic electrolyte. It is somehow desired to have an actuator that is independent of the applied solvent in the same actuation direction. In this research we made PPy/DBS with the addition of phosphorus tungsten acid, forming PPyPT films, as well with included carbide derived carbon (CDC) resulting in PPyCDC films. The solvent in electropolymerization was changed from an aqueous ethylene glycol mixture to pure EG forming PPyPT-EG and PPyCDC-EG composites. Our goal in this study was to investigate the linear actuation properties of PPy composites applying sodium perchlorate in aqueous (NaClO4-aq) and propylene carbonate (NaClO4-PC) electrolytes. Cyclic voltammetry and square potential steps in combination with electro-chemo-mechanical-deformation (ECMD) measurements of PPy composite films were performed. The PPyPT and PPyCDC had mixed ion-actuation in NaClO4-PC while in NaClO4-aq expansion at reduction (cation-driven) was observed. Those novel PPy composites electropolymerized in EG solvent showed independently which solvent applied mainly expansion at reduction (cation-driven actuator). Chronopotentiometric measurements were performed on all composites, revealing excellent specific capacitance up to 190 F g-1 for PPyCDC-EG (best capacitance retention of 90 % after 1000 cycles) and 130 F g-1 for PPyPT-EG in aqueous electrolyte. The films were characterized by scanning electron microscopy (SEM), Raman, Fourier-transform infrared (FTIR) and energy dispersive X-ray spectroscopy (EDX).
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Affiliation(s)
- Chau B. Tran
- Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam;
| | - Zane Zondaka
- Intelligent Materials and Systems Lab, Faculty of Science and Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia;
| | - Quoc Bao Le
- Conducting Polymers in Composites and Applications Research Group, Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam;
| | - Bharath Kumar Velmurugan
- Department of Medical Laboratory Science and Biotechnology, Asia University, Taichung 413, Taiwan;
| | - Rudolf Kiefer
- Conducting Polymers in Composites and Applications Research Group, Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam;
- Correspondence: ; Tel.: +886-905605515
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Otero TF. Electroactive macromolecular motors as model materials of ectotherm muscles. RSC Adv 2021; 11:21489-21506. [PMID: 35478837 PMCID: PMC9034182 DOI: 10.1039/d1ra02573b] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 06/10/2021] [Indexed: 12/21/2022] Open
Abstract
The electrochemical reaction in liquid electrolytes of conducting polymers, carbon nanotubes, graphenes, among other materials, replicates the active components (macromolecular electro-chemical motors, ions and solvent) and volume variation of the sarcomere in any natural muscles during actuation, allowing the development of electro-chemo-mechanical artificial muscles. Materials, reactions and artificial muscles have been used as model materials, model reactions and model devices of the muscles from ectotherm animals. We present in this perspective the experimental results and a quantitative description of the thermal influence on the reaction extension and energetic achievements of those muscular models using different experimental methodologies. By raising the temperature for 40 °C keeping the extension of the muscular movement the cooperative actuation of the macromolecular motors harvest, saving chemical energy, up to 60% of the reaction energy from the thermal environment. The synergic thermal influence on either, the reaction rate (Arrhenius), the conformational movement rates of the motors (ESCR model) and the diffusion coefficients of ions across polymer matrix (WLF equation) can support the physical chemical foundations for the selection by nature of ectotherm muscles. Macromolecular motors act, simultaneously, as electro-chemo-mechanical and thermo-mechanical transducers. Technological and biological perspectives are presented.
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Affiliation(s)
- Toribio Fernández Otero
- Technical University of Cartagena, Laboratory of Electrochemistry, Intelligent Materials and Devices, Department of Chemical and Environmental Engineering Campus Alfonso XIII 30203 Cartagena Spain
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Kiefer R, Nguyen NT, Le QB, Anbarjafari G, Tamm T. Antagonist Concepts of Polypyrrole Actuators: Bending Hybrid Actuator and Mirrored Trilayer Linear Actuator. Polymers (Basel) 2021; 13:polym13060861. [PMID: 33799659 PMCID: PMC7999340 DOI: 10.3390/polym13060861] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/09/2021] [Accepted: 03/09/2021] [Indexed: 01/13/2023] Open
Abstract
Following the natural muscle antagonist actuation principle, different adaptations for "artificial muscles" are introduced in this work. Polypyrrole (PPy) films of different polymerization techniques (potentiostatic and galvanostatic) were analyzed and their established responses were combined in several ways, resulting in beneficial actuation modes. A consecutive "one-pot" electrosynthesis of two layers with the different deposition regimes resulted in an all-PPy bending hybrid actuator. While in most cases the mixed-ion activity of conductive polymers has been considered a problem or a drawback, here for the first time, the nearly equal expansions upon oxidation and reduction of carefully selected conditions further allowed to fabricate a "mirrored" trilayer laminate, which behaved as a linear actuator.
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Affiliation(s)
- Rudolf Kiefer
- Conducting Polymers in Composites and Applications Research Group, Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam;
- Correspondence:
| | - Ngoc Tuan Nguyen
- Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam;
| | - Quoc Bao Le
- Conducting Polymers in Composites and Applications Research Group, Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam;
| | | | - Tarmo Tamm
- Intelligent Materials and Systems Lab, Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia;
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9
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Otero TF. Towards artificial proprioception from artificial muscles constituted by self-sensing multi-step electrochemical macromolecular motors. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2020.137576] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Sall ML, Diaw AKD, Gningue-Sall D, Efremova Aaron S, Aaron JJ. Toxic heavy metals: impact on the environment and human health, and treatment with conducting organic polymers, a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:29927-29942. [PMID: 32506411 DOI: 10.1007/s11356-020-09354-3] [Citation(s) in RCA: 193] [Impact Index Per Article: 48.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Accepted: 05/18/2020] [Indexed: 04/16/2023]
Abstract
Water pollution by heavy metals has many human origins, such as the burning of fossil fuels, exhaust gases of vehicles, mining, agriculture, and incineration of solid and liquid wastes. Heavy metals also occur naturally, due to volcanoes, thermal springs activity, erosion, infiltration, etc. This water contamination is a threat for living beings because most heavy metals are toxic to humans and to aquatic life. Hence, it is important to find effective techniques for removing these contaminants in order to reduce the level of pollution of the natural waters. In this work, we have reviewed the toxicity of several heavy metals (mercury, lead, cadmium, chromium, nickel), their impact on the environment and human health, and the synthesis and characterization methods of conducting organic polymers (COPs) utilized for the removal of heavy metals from the environment. Therefore, this review was essentially aimed to present recent works and methods (2000-2020) on the environmental impact and toxicity of heavy metals and on the removal of toxic heavy metals, using chemically and/or electrochemically synthesized COPs. We have also stressed the great interest of COPs for the removal of toxic heavy metals from waters.
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Affiliation(s)
- Mohamed Lamine Sall
- Laboratoire de Chimie Physique Organique et d'Analyse Environementale (LCPOAE), Département de Chimie, Université Cheikh Anta Diop, BP 5005, Dakar-Fann, Senegal
- Laboratoire Géomatériaux et Environnement (LGE), Université Paris-Est, 5 Boulevard Descartes, Champs-sur-Marne, 77454, Marne la Vallée Cedex 2, France
| | - Abdou Karim Diagne Diaw
- Laboratoire de Chimie Physique Organique et d'Analyse Environementale (LCPOAE), Département de Chimie, Université Cheikh Anta Diop, BP 5005, Dakar-Fann, Senegal
| | - Diariatou Gningue-Sall
- Laboratoire de Chimie Physique Organique et d'Analyse Environementale (LCPOAE), Département de Chimie, Université Cheikh Anta Diop, BP 5005, Dakar-Fann, Senegal
| | - Snezana Efremova Aaron
- Department of Medical and Experimental Biochemistry, Faculty of Medicine, Ss. Cyril & Methodius University, Skopje, North Macedonia
| | - Jean-Jacques Aaron
- Laboratoire Géomatériaux et Environnement (LGE), Université Paris-Est, 5 Boulevard Descartes, Champs-sur-Marne, 77454, Marne la Vallée Cedex 2, France.
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Harjo M, Järvekülg M, Tamm T, Otero TF, Kiefer R. Concept of an artificial muscle design on polypyrrole nanofiber scaffolds. PLoS One 2020; 15:e0232851. [PMID: 32392238 PMCID: PMC7213722 DOI: 10.1371/journal.pone.0232851] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 04/22/2020] [Indexed: 01/25/2023] Open
Abstract
Here we present the synthesis and characterization of two new conducting materials having a high electro-chemo-mechanical activity for possible applications as artificial muscles or soft smart actuators in biomimetic structures. Glucose-gelatin nanofiber scaffolds (CFS) were coated with polypyrrole (PPy) first by chemical polymerization followed by electrochemical polymerization doped with dodecylbenzensulfonate (DBS-) forming CFS-PPy/DBS films, or with trifluoromethanesulfonate (CF3SO3-, TF) giving CFS-PPy/TF films. The composition, electronic and ionic conductivity of the materials were determined using different techniques. The electro-chemo-mechanical characterization of the films was carried out by cyclic voltammetry and square wave potential steps in bis(trifluoromethane)sulfonimide lithium solutions of propylene carbonate (LiTFSI-PC). Linear actuation of the CFS-PPy/DBS material exhibited 20% of strain variation with a stress of 0.14 MPa, rather similar to skeletal muscles. After 1000 cycles, the creeping effect was as low as 0,2% having a good long-term stability showing a strain variation per cycle of -1.8% (after 1000 cycles). Those material properties are excellent for future technological applications as artificial muscles, batteries, smart membranes, and so on.
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Affiliation(s)
- Madis Harjo
- Intelligent Materials and Systems Lab, Faculty of Science and Technology, University of Tartu, Tartu, Estonia
| | - Martin Järvekülg
- Institute of Physics, Faculty of Science and Technology, University of Tartu, Tartu, Estonia
| | - Tarmo Tamm
- Intelligent Materials and Systems Lab, Faculty of Science and Technology, University of Tartu, Tartu, Estonia
| | - Toribio F. Otero
- Centre for Electrochemistry and Intelligent Materials (CEMI), Universidad Politécnica de Cartagena, Cartagena, Murcia, Spain
| | - Rudolf Kiefer
- Conducting polymers in composites and applications Research Group, Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam
- * E-mail:
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Harjo M, Torop J, Järvekülg M, Tamm T, Kiefer R. Electrochemomechanical Behavior of Polypyrrole-Coated Nanofiber Scaffolds in Cell Culture Medium. Polymers (Basel) 2019; 11:E1043. [PMID: 31200448 PMCID: PMC6630290 DOI: 10.3390/polym11061043] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/07/2019] [Accepted: 06/12/2019] [Indexed: 11/16/2022] Open
Abstract
Glucose-gelatin nanofiber scaffolds were made conductive and electroactive by chemical (conductive fiber scaffolds, CFS) and additionally electrochemical polypyrrole deposition (doped with triflouromethanesulfonate CF3SO3-, CFS-PPyTF). Both materials were investigated in their linear actuation properties in cell culture medium (CCM), as they could be potential electro-mechanically activated cell growth substrates. Independent of the deposition conditions, both materials showed relatively stable cation-driven actuation in CCM, based on the flux of mainly Na+ ions from CCM. The surprising result was attributed to re-doping by sulfate anions in CCM, as also indicated by energy-dispersive X-ray (EDX) spectroscopy results. Overall, the electrochemically coated material outperformed the one with just chemical coating in conductivity, charge density and actuation response.
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Affiliation(s)
- Madis Harjo
- Intelligent Materials and Systems Lab, Faculty of Science and Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia.
| | - Janno Torop
- Intelligent Materials and Systems Lab, Faculty of Science and Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia.
| | - Martin Järvekülg
- Institute of Physics, Faculty of Science and Technology, University of Tartu, W. Ostwaldi Str 1, 50411 Tartu, Estonia.
| | - Tarmo Tamm
- Intelligent Materials and Systems Lab, Faculty of Science and Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia.
| | - Rudolf Kiefer
- Conducting polymers in composites and applications Research Group, Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam.
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Khuyen NQ, Zondaka Z, Harjo M, Torop J, Tamm T, Kiefer R. Comparative Analysis of Fluorinated Anions for Polypyrrole Linear Actuator Electrolytes. Polymers (Basel) 2019; 11:E849. [PMID: 31083347 PMCID: PMC6571709 DOI: 10.3390/polym11050849] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 05/06/2019] [Accepted: 05/07/2019] [Indexed: 11/19/2022] Open
Abstract
Either as salts or room temperature ionic liquids, fluorinated anion-based electrolytes have been a common choice for ionic electroactive polymer actuators, both linear and bending. In the present work, propylene carbonate solutions of four electrolytes of the three hugely popular anions-triflouromethanesulfonate, bis(trifluoromethane)sulfonimide, and hexafluorophosphate were compared and evaluated in polypyrrole linear actuators. The actuation direction, the characteristics-performance relations influence the behavior of the actuators. Isotonic Electro-chemo-mechanical deformation (ECMD) measurements were performed to study the response of the PPy/DBS samples. The highest strain for pristine PPy/DBS linear actuators was found in range of 21% for LiTFSI, while TBAPF6 had the least cation involvement, suggesting the potential for application in durable and controllable actuators. Interesting cation effects on the actuation of the same anions (CF3SO3-) were also observed.
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Affiliation(s)
- Nguyen Quang Khuyen
- Conducting Polymers in Composites and Applications Research Group, Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
| | - Zane Zondaka
- Intelligent Materials and Systems Lab, Faculty of Science and Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia.
| | - Madis Harjo
- Intelligent Materials and Systems Lab, Faculty of Science and Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia.
| | - Janno Torop
- Intelligent Materials and Systems Lab, Faculty of Science and Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia.
| | - Tarmo Tamm
- Intelligent Materials and Systems Lab, Faculty of Science and Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia.
| | - Rudolf Kiefer
- Conducting Polymers in Composites and Applications Research Group, Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam.
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Baleg AA, Masikini M, John SV, Williams AR, Jahed N, Baker P, Iwuoha E. Conducting Polymers and Composites. POLYMERS AND POLYMERIC COMPOSITES: A REFERENCE SERIES 2019:551-604. [DOI: 10.1007/978-3-319-95987-0_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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16
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Kiefer R, Kesküla A, Martinez JG, Anbarjafari G, Torop J, Otero TF. Interpenetrated triple polymeric layer as electrochemomechanical actuator: Solvent influence and diffusion coefficient of counterions. Electrochim Acta 2017. [DOI: 10.1016/j.electacta.2017.01.191] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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17
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Fuchiwaki M, Martinez JG, Fernandez Otero T. Asymmetric Bilayer Muscles: Cooperative Actuation, Dynamic Hysteresis, and Creeping in NaPF6 Aqueous Solutions. ChemistryOpen 2016; 5:369-74. [PMID: 27547647 PMCID: PMC4981058 DOI: 10.1002/open.201600012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Indexed: 11/17/2022] Open
Abstract
Three bilayer muscles [polypyrrole-paraphenolsulfonic acid/polypyrrole-dodecylbenzensulfonic acid (PPy-HpPS/PPy-DBS) asymmetric bilayer, PPy-HpPS/tape, and PPy-DBS/tape] were characterized during potential cycling in NaPF6 aqueous solutions. In parallel, the angular displacement of the muscle was video-recorded. The dynamo-voltammetric (angle-potential) and coulo-dynamic (charge-potential) results give the reaction-driven ionic exchanges in each PPy film. Electrochemical reactions drive the exchange of anions from the PPy-HpPS layer and cations from the PPy-DBS layer. This means that both layers from the asymmetric bilayer follow complementary volume changes (swelling/shrinking or shrinking/swelling), owing to complementary ionic exchanges (entrance/expulsion) driven by the bilayer oxidation or reduction. The result is a cooperative actuation; the bending amplitude described by the asymmetric bilayer muscle is one order of magnitude larger than those attained from each of the conducting polymer/tape muscles. The cooperative actuation almost eliminates creeping effects. A large dynamical hysteresis persists, which can be attributed to an irreversible reaction of the organic acid components at high overpotentials.
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Affiliation(s)
- Masaki Fuchiwaki
- Department of Mechanical Information Science and TechnologyKyushu Institute of Technology680-4 Kawazu IizukaFukuoka820-8502Japan
| | - Jose G. Martinez
- Center for Electrochemistry and Intelligent MaterialsUniversidad Politécnica de CartagenaAulario II, C/Carlos III, s/n30203CartagenaSpain
| | - Toribio Fernandez Otero
- Center for Electrochemistry and Intelligent MaterialsUniversidad Politécnica de CartagenaAulario II, C/Carlos III, s/n30203CartagenaSpain
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Fuchiwaki M, Martinez JG, Otero TF. Asymmetric Bilayer Muscles. Cooperative and Antagonist Actuation. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2016.02.104] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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19
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Otero TF, Schumacher J, Pascual VH. Construction and coulodynamic characterization of PPy-DBS-MWCNT/tape bilayer artificial muscles. RSC Adv 2016. [DOI: 10.1039/c6ra13806c] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A bilayer full polymeric artificial muscle comprised of electrogenerated PPy-DBS-MWCNT composite and tape was constructed and electrochemical and electrodynamical characterized.
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Affiliation(s)
- Toribio F. Otero
- Laboratory of Electrochemistry and Intelligent Materials
- Technical University of Cartagena
- Cartagena
- Spain
| | | | - Victor H. Pascual
- Laboratory of Electrochemistry and Intelligent Materials
- Technical University of Cartagena
- Cartagena
- Spain
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Kivilo A, Zondaka Z, Kesküla A, Rasti P, Tamm T, Kiefer R. Electro-chemo-mechanical deformation properties of polypyrrole/dodecylbenzenesulfate linear actuators in aqueous and organic electrolyte. RSC Adv 2016. [DOI: 10.1039/c6ra20766a] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The immobilization of dodecylbenzenesulfonate (DBS−) in polypyrrole (PPy) during electropolymerization is typically expected to lead to cation-driven activity. Here we demonstrate that the actuation direction changed by using same electrolyte but different solvent.
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Affiliation(s)
- A. Kivilo
- Intelligent Materials and Systems Lab
- Institute of Technology
- University of Tartu
- 50411 Tartu
- Estonia
| | - Z. Zondaka
- Intelligent Materials and Systems Lab
- Institute of Technology
- University of Tartu
- 50411 Tartu
- Estonia
| | - A. Kesküla
- Intelligent Materials and Systems Lab
- Institute of Technology
- University of Tartu
- 50411 Tartu
- Estonia
| | - P. Rasti
- iCV Research Group
- Institute of Technology
- University of Tartu
- 50411 Tartu
- Estonia
| | - T. Tamm
- Intelligent Materials and Systems Lab
- Institute of Technology
- University of Tartu
- 50411 Tartu
- Estonia
| | - R. Kiefer
- Intelligent Materials and Systems Lab
- Institute of Technology
- University of Tartu
- 50411 Tartu
- Estonia
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Kerr-Phillips TE, Woehling V, Agniel R, Nguyen GTM, Vidal F, Kilmartin P, Plesse C, Travas-Sejdic J. Electrospun rubber fibre mats with electrochemically controllable pore sizes. J Mater Chem B 2015; 3:4249-4258. [DOI: 10.1039/c5tb00239g] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Electroactive, elastomeric, microfiber mats that show controllable pore size variation upon electrochemical stimulation are produced from semi-interpenetrating polymer networks (s-IPNs).
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Affiliation(s)
- Thomas E. Kerr-Phillips
- Polymer Electronics Research Centre (PERC)
- School of Chemical Sciences
- University of Auckland
- Auckland
- New Zealand
| | - Vincent Woehling
- LPPI-EA2528
- Institut des Materiaux
- Cergy-Pontoise cedex 95031
- France
| | - Remi Agniel
- LPPI-EA2528
- Institut des Materiaux
- Cergy-Pontoise cedex 95031
- France
| | | | - Frederic Vidal
- LPPI-EA2528
- Institut des Materiaux
- Cergy-Pontoise cedex 95031
- France
| | - Paul Kilmartin
- Polymer Electronics Research Centre (PERC)
- School of Chemical Sciences
- University of Auckland
- Auckland
- New Zealand
| | - Cédric Plesse
- LPPI-EA2528
- Institut des Materiaux
- Cergy-Pontoise cedex 95031
- France
| | - Jadranka Travas-Sejdic
- Polymer Electronics Research Centre (PERC)
- School of Chemical Sciences
- University of Auckland
- Auckland
- New Zealand
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Ambipolar Freestanding Triphenylamine/Fullerene Thin-film by Electrochemical Deposition and Its Read-Writable Properties by Electrochemical Treatments. Electrochim Acta 2014. [DOI: 10.1016/j.electacta.2013.11.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Travas-Sejdic J, Aydemir N, Kannan B, Williams DE, Malmström J. Intrinsically conducting polymer nanowires for biosensing. J Mater Chem B 2014; 2:4593-4609. [DOI: 10.1039/c4tb00598h] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The fabrication of conductive polymer nanowires and their sensing of nucleic acids, proteins and pathogens is reviewed in this feature article.
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Affiliation(s)
- J. Travas-Sejdic
- School of Chemical Sciences
- University of Auckland
- Auckland 1142, New Zealand
- MacDiarmid Institute for Advanced Materials and Nanotechnology
- Wellington 6140, New Zealand
| | - N. Aydemir
- School of Chemical Sciences
- University of Auckland
- Auckland 1142, New Zealand
- MacDiarmid Institute for Advanced Materials and Nanotechnology
- Wellington 6140, New Zealand
| | - B. Kannan
- Revolution Fibres Ltd
- , New Zealand
- School of Chemical Sciences
- University of Auckland
- Auckland 1142, New Zealand
| | - D. E. Williams
- School of Chemical Sciences
- University of Auckland
- Auckland 1142, New Zealand
- MacDiarmid Institute for Advanced Materials and Nanotechnology
- Wellington 6140, New Zealand
| | - J. Malmström
- School of Chemical Sciences
- University of Auckland
- Auckland 1142, New Zealand
- MacDiarmid Institute for Advanced Materials and Nanotechnology
- Wellington 6140, New Zealand
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Sharma M, Svirskis D, Garg S. Advances in Drug-delivery Systems Based on Intrinsically Conducting Polymers. SMART MATERIALS FOR DRUG DELIVERY 2013. [DOI: 10.1039/9781849736800-00283] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Intrinsically conducting polymers (ICPs) are organic polymers with unique capabilities including the ability to conduct electricity. The release of drugs from ICP-based drug delivery systems can be controlled using electrical signaling to alter the redox state of the ICP, leading to subsequent changes in polymer charge and volume. The increasing use of ICPs in drug delivery systems can be attributed to their biocompatible nature and the ability to regulate drug release electrically. Drug can be easily incorporated into these polymers by physical and chemical means. As the release of the drugs from ICPs is in accordance with electrical stimulus the therapeutic effect can be maximized with a reduction in the side effects. In this chapter a general overview of ICPs, their electrochemical properties and the techniques used to characterize these materials with specifics pertaining to drug delivery is provided. Emphasis is given to advances in methods and technology to enhance the drug-loading capacity of these polymers and to achieve precise controlled therapy. The chapter discusses some of the exciting applications of ICPs as devices for controlled delivery of drugs to desired locations.
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Affiliation(s)
- Manisha Sharma
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland New Zealand
| | - Darren Svirskis
- School of Pharmacy, Faculty of Medical and Health Sciences, University of Auckland New Zealand
| | - Sanjay Garg
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide Australia
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Sharma M, Waterhouse GIN, Loader SWC, Garg S, Svirskis D. High surface area polypyrrole scaffolds for tunable drug delivery. Int J Pharm 2013; 443:163-8. [PMID: 23318368 DOI: 10.1016/j.ijpharm.2013.01.006] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 01/04/2013] [Indexed: 11/19/2022]
Abstract
Intrinsically conducting polymers such as polypyrrole (PPy) are viable platforms for efficient drug delivery, where release rates can be tuned by external electrical stimulus. In this study, the successful fabrication of 3-dimensionally ordered macroporous PPy inverse opal thin films is described, and the viability of such films for controlled drug release evaluated in vitro. The PPy inverse opal thin films were obtained by electropolymerization of PPy through the interstitial voids of a colloidal crystal template composed of poly(methyl methacrylate) colloids of diameter ∼430 nm. Chemical etching of the template yielded macroporous PPy inverse opal scaffolds. The model drug risperidone was loaded into the PPy inverse opal films, and then entrapped by electropolymerization of a non-porous PPy overlayer. The morphology and chemical composition of the PPy scaffolds were evaluated by SEM and FTIR spectroscopy, respectively. The high surface area PPy inverse opal scaffolds exhibited enhanced drug loading and releasing capabilities compared to conventional non-porous PPy films. Drug release profiles could be modified by applying electrical stimulus, which caused actuation of the porous polypyrrole films. The proposed delivery system may find use as an implantable device where drug release can be electrically tuned according to patient requirements.
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Affiliation(s)
- Manisha Sharma
- School of Pharmacy, University of Auckland, Auckland, New Zealand
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Otero TF, Martinez JG. Biomimetic intracellular matrix (ICM) materials, properties and functions. Full integration of actuators and sensors. J Mater Chem B 2013; 1:26-38. [DOI: 10.1039/c2tb00176d] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Otero T, Martinez J, Arias-Pardilla J. Biomimetic electrochemistry from conducting polymers. A review. Electrochim Acta 2012. [DOI: 10.1016/j.electacta.2012.03.097] [Citation(s) in RCA: 236] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Spires JB, Peng H, Williams D, Travas-Sejdic J. An improved terthiophene conducting polymer for DNA-sensing. Electrochim Acta 2011. [DOI: 10.1016/j.electacta.2011.09.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Arias-Pardilla J, Otero T, Yu HH. Electropolymerization and characterization of COOH-functionalized poly(3,4-ethylenedioxythiophene): Ionic exchanges. Electrochim Acta 2011. [DOI: 10.1016/j.electacta.2011.09.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Spires JB, Peng H, Williams D, Travas-Sejdic J. The solvent-induced collapse of a redox-active conducting polymer and the consequence on its DNA-sensing ability. J Electroanal Chem (Lausanne) 2011. [DOI: 10.1016/j.jelechem.2011.02.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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31
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Laslau C, Williams DE, Wright BE, Travas-Sejdic J. Measuring the Ionic Flux of an Electrochemically Actuated Conducting Polymer Using Modified Scanning Ion Conductance Microscopy. J Am Chem Soc 2011; 133:5748-51. [DOI: 10.1021/ja200639z] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sensing and tactile artificial muscles from reactive materials. SENSORS 2010; 10:2638-74. [PMID: 22319265 PMCID: PMC3274195 DOI: 10.3390/s100402638] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2010] [Revised: 02/17/2010] [Accepted: 03/02/2010] [Indexed: 11/16/2022]
Abstract
Films of conducting polymers can be oxidized and reduced in a reversible way. Any intermediate oxidation state determines an electrochemical equilibrium. Chemical or physical variables acting on the film may modify the equilibrium potential, so that the film acts as a sensor of the variable. The working potential of polypyrrole/DBSA (Dodecylbenzenesulfonic acid) films, oxidized or reduced under constant currents, changes as a function of the working conditions: electrolyte concentration, temperature or mechanical stress. During oxidation, the reactive material is a sensor of the ambient, the consumed electrical energy being the sensing magnitude. Devices based on any of the electrochemical properties of conducting polymers must act simultaneously as sensors of the working conditions. Artificial muscles, as electrochemical actuators constituted by reactive materials, respond to the ambient conditions during actuation. In this way, they can be used as actuators, sensing the surrounding conditions during actuation. Actuating and sensing signals are simultaneously included by the same two connecting wires.
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Kiefer R, Bowmaker GA, Kilmartin PA, Travas-Sejdic J. Effect of polymerization potential on the actuation of free standing poly-3,4-ethylenedioxythiophene films in a propylene carbonate electrolyte. Electrochim Acta 2010. [DOI: 10.1016/j.electacta.2009.09.034] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Otero TF. Soft, wet, and reactive polymers. Sensing artificial muscles and conformational energy. ACTA ACUST UNITED AC 2009. [DOI: 10.1039/b809485c] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Martins N, Moura e Silva T, Montemor M, Fernandes J, Ferreira M. Electrodeposition and characterization of polypyrrole films on aluminium alloy 6061-T6. Electrochim Acta 2008. [DOI: 10.1016/j.electacta.2008.01.059] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Sui J, Travas-Sejdic J, Chu SY, Li KC, Kilmartin PA. The actuation behavior and stability of p-toluene sulfonate doped polypyrrole films formed at different deposition current densities. J Appl Polym Sci 2008. [DOI: 10.1002/app.29119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Kiefer R, Bowmaker GA, Cooney RP, Kilmartin PA, Travas-Sejdic J. Cation driven actuation for free standing PEDOT films prepared from propylene carbonate electrolytes containing TBACF3SO3. Electrochim Acta 2008. [DOI: 10.1016/j.electacta.2007.10.033] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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