Resulting from its wide range of beneficial properties, the conjugated conducting polymer poly(3,4‐ethylenedioxythiophene) (PEDOT) is a promising material in a number of emerging applications. These ...material properties, particularly promising in the field of bioelectronics, include its well‐known high‐degree of mechanical flexibility, stability, and high conductivity. However, perhaps the most advantageous property is its ease of fabrication: namely, low‐cost and straight‐forward deposition processes. PEDOT processing is generally carried out at low temperatures with simple deposition techniques, allowing for significant customization of the material properties through, as highlighted in this review, both process parameter variation and the addition of numerous additives. Here we aim to review the role of PEDOT in addressing an assortment of mechanical and electronic requirements as a function of the conditions used to cast or polymerize the films, and the addition of additives such as surfactants and secondary dopants. Contemporary bioelectronic research examples investigating and utilizing the effects of these modifications will be highlighted.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A photolithographic process was used to integrate the conducting polymer poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) with parylene C, yielding highly conformable electrode ...arrays that were only four micrometers thick (shown here to conform to the midrib of a small leaf). The arrays were sufficiently self‐supporting to allow in vivo evaluation in rats, yielding high‐quality electrocorticography recordings.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
43.
Bioelectronic neural pixel Jonsson, Amanda; Inal, Sahika; Uguz, Ilke ...
Proceedings of the National Academy of Sciences - PNAS,
08/2016, Volume:
113, Issue:
34
Journal Article
Peer reviewed
Open access
Local control of neuronal activity is central to many therapeutic strategies aiming to treat neurological disorders. Arguably, the best solution would make use of endogenous highly localized and ...specialized regulatory mechanisms of neuronal activity, and an ideal therapeutic technology should sense activity and deliver endogenous molecules at the same site for the most efficient feedback regulation. Here, we address this challenge with an organic electronic multifunctional device that is capable of chemical stimulation and electrical sensing at the same site, at the single-cell scale. Conducting polymer electrodes recorded epileptiform discharges induced in mouse hippocampal preparation. The inhibitory neurotransmitter, γ-aminobutyric acid (GABA), was then actively delivered through the recording electrodes via organic electronic ion pump technology. GABA delivery stopped epileptiform activity, recorded simultaneously and colocally. This multifunctional “neural pixel” creates a range of opportunities, including implantable therapeutic devices with automated feedback, where locally recorded signals regulate local release of specific therapeutic agents.
The development of electronics capable of interfacing with the nervous system is a rapidly advancing field with applications in basic science and clinical translation. Devices containing arrays of ...electrodes can be used in the study of cells grown in culture or can be implanted into damaged or dysfunctional tissue to restore normal function. While devices are typically designed and used exclusively for one of these two purposes, there have been increasing efforts in developing implantable electrode arrays capable of housing cultured cells, referred to as biohybrid implants. Once implanted, the cells within these implants integrate into the tissue, serving as a mediator of the electrode–tissue interface. This biological component offers unique advantages to these implant designs, providing better tissue integration and potentially long‐term stability. Herein, an overview of current research into biohybrid devices, as well as the historical background that led to their development are provided, based on the host anatomical location for which they are designed (CNS, PNS, or special senses). Finally, a summary of the key challenges of this technology and potential future research directions are presented.
Electronics capable of interfacing with the nervous system are rapidly evolving. Biohybrid implants represent a new type of neural interface, combining implantable electrodes technology and cell transplantation. An overview of biohybrid interfaces, with a classification based on the host anatomical location is provided. A summary of the key challenges and the potential future research directions are also presented.
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We report the electronic structure and diverse applications of a highly luminescent ionic transition metal complex, Ir(dF(CF3)ppy)2(dtbbpy)(PF6) (where dF(CF3)ppy = ...2-(2,4-difluorophenyl)-5-trifluoromethylpyridine and dtbbpy = 4,4‘-di-tert-butyl-2,2‘-dipyridyl). The large HOMO−LUMO gap (ΔE = 3.06 V) enabled high-energy electroluminescence from the complex. Single-layer devices were fabricated and found to emit blue-green light (500 nm). The strong reducing strength of the excited state (E*ox = 1.21 V) enabled effective catalysis of the photoinduced reduction of H2O to H2. It was found that the relative quantum yield of hydrogen was over an order of magnitude improved from the standard photosensitizer Ru(dmphen)3 2+ (dmphen = 4,7-dimethyl-1,10-phenanthroline).
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Conducting polymers take control of the field McLeod, Robert R; Malliaras, George G
Proceedings of the National Academy of Sciences - PNAS,
01/2024, Volume:
121, Issue:
4
Journal Article
The response of PEDOT:PSS planar electrochemical transistors to H2O2 can be tuned by varying the ratio between the areas of the channel and the gate electrode. Devices with small gates show lower ...background signal and higher sensitivity. The detection range, on the other hand, is found to be rather independent of the gate/channel area ratio.
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Efficient transport of both ionic and electronic charges in conjugated polymers (CPs) has enabled a wide range of novel electrochemical devices spanning applications from energy storage to ...bioelectronic devices. In this Perspective, we provide an overview of the fundamental physical processes which underlie the operation of mixed conducting polymer (MCP) devices. While charge injection and transport have been studied extensively in both ionic and electronic conductors, translating these principles to mixed conducting systems proves challenging due to the complex relationships among the individual materials properties. We break down the process of electrochemical (de)doping, the basic feature exploited in mixed conducting devices, into its key steps, highlighting recent advances in the study of these physical processes in the context of MCPs. Furthermore, we identify remaining challenges in further extending fundamental understanding of MCP-based device operation. Ultimately, a deeper understanding of the elementary processes governing operation in MCPs will drive the advancement in both materials design and device performance.
Mixed ionic-electronic conduction is a critical feature in a wide range of emerging electrochemical devices based on conjugated polymers exploiting transport, coupling, and charge carrier concentration modulation of both electronic and ionic charges.
•The surface ageing of PEDOT:PSS has been studied during 6 months.•Impact of temperature, cross-linker concentration and storage conditions have been monitored.•The interface undergoes significant ...reorganization regardless of the concentration of cross-linker.•The temperature (37 °C) induces irreversible changes in the composition of film even in presence of cross-linker.•Pristine and cross-linked polymers need two to four months to stabilize their interface.
Known for its electric properties, poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) has emerged as a good candidate for organic electronics and more recently for bio-applications. Despite its growing use in engineering applications, little is known about the stability in time of its interface properties. Here, we consider the surface ageing of PEDOT:PSS when it is stored in environments with various relative humidity and temperature conditions and as a function of the cross-linking agent’s (3-glycidoxypropyltrimethoxysilane) concentration. Our systematic wettability study over 6 months reveals that the PEDOT:PSS interface undergoes significant reorganization and some irreversible changes on these timescales regardless of the concentration of cross-linker added.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP