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Borriello M, Tarabella G, D’Angelo P, Liboà A, Barra M, Vurro D, Lombari P, Coppola A, Mazzella E, Perna AF, Ingrosso D. Lab on a Chip Device for Diagnostic Evaluation and Management in Chronic Renal Disease: A Change Promoting Approach in the Patients' Follow Up. BIOSENSORS 2023; 13:373. [PMID: 36979584 PMCID: PMC10046018 DOI: 10.3390/bios13030373] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/06/2023] [Accepted: 03/10/2023] [Indexed: 06/18/2023]
Abstract
Lab-on-a-chip (LOC) systems are miniaturized devices aimed to perform one or several analyses, normally carried out in a laboratory setting, on a single chip. LOC systems have a wide application range, including diagnosis and clinical biochemistry. In a clinical setting, LOC systems can be associated with the Point-of-Care Testing (POCT) definition. POCT circumvents several steps in central laboratory testing, including specimen transportation and processing, resulting in a faster turnaround time. Provider access to rapid test results allows for prompt medical decision making, which can lead to improved patient outcomes, operational efficiencies, patient satisfaction, and even cost savings. These features are particularly attractive for healthcare settings dealing with complicated patients, such as those affected by chronic kidney disease (CKD). CKD is a pathological condition characterized by progressive and irreversible structural or functional kidney impairment lasting for more than three months. The disease displays an unavoidable tendency to progress to End Stage Renal Disease (ESRD), thus requiring renal replacement therapy, usually dialysis, and transplant. Cardiovascular disease (CVD) is the major cause of death in CKD, with a cardiovascular risk ten times higher in these patients than the rate observed in healthy subjects. The gradual decline of the kidney leads to the accumulation of uremic solutes, with negative effect on organs, especially on the cardiovascular system. The possibility to monitor CKD patients by using non-invasive and low-cost approaches could give advantages both to the patient outcome and sanitary costs. Despite their numerous advantages, POCT application in CKD management is not very common, even if a number of devices aimed at monitoring the CKD have been demonstrated worldwide at the lab scale by basic studies (low Technology Readiness Level, TRL). The reasons are related to both technological and clinical aspects. In this review, the main technologies for the design of LOCs are reported, as well as the available POCT devices for CKD monitoring, with a special focus on the most recent reliable applications in this field. Moreover, the current challenges in design and applications of LOCs in the clinical setting are briefly discussed.
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Affiliation(s)
- Margherita Borriello
- Department of Precision Medicine, University of Campania “Luigi Vanvitelli”, via L. De Crecchio, 7, 80138 Naples, Italy
| | | | | | - Aris Liboà
- IMEM-CNR, Parco Area delle Scienze 37/A, 43124 Parma, Italy; (G.T.)
| | - Mario Barra
- CNR-SPIN, c/o Dipartimento di Fisica “Ettore Pancini”, P.le Tecchio, 80, 80125 Naples, Italy
| | - Davide Vurro
- IMEM-CNR, Parco Area delle Scienze 37/A, 43124 Parma, Italy; (G.T.)
| | - Patrizia Lombari
- Department of Precision Medicine, University of Campania “Luigi Vanvitelli”, via L. De Crecchio, 7, 80138 Naples, Italy
| | - Annapaola Coppola
- Department of Precision Medicine, University of Campania “Luigi Vanvitelli”, via L. De Crecchio, 7, 80138 Naples, Italy
| | - Elvira Mazzella
- Department of Translational Medical Science, University of Campania “Luigi Vanvitelli”, via Via Pansini, Bldg 17, 80131 Naples, Italy
| | - Alessandra F. Perna
- Department of Translational Medical Science, University of Campania “Luigi Vanvitelli”, via Via Pansini, Bldg 17, 80131 Naples, Italy
| | - Diego Ingrosso
- Department of Precision Medicine, University of Campania “Luigi Vanvitelli”, via L. De Crecchio, 7, 80138 Naples, Italy
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Balakrishnan G, Song J, Mou C, Bettinger CJ. Recent Progress in Materials Chemistry to Advance Flexible Bioelectronics in Medicine. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2106787. [PMID: 34751987 PMCID: PMC8917047 DOI: 10.1002/adma.202106787] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 10/15/2021] [Indexed: 05/09/2023]
Abstract
Designing bioelectronic devices that seamlessly integrate with the human body is a technological pursuit of great importance. Bioelectronic medical devices that reliably and chronically interface with the body can advance neuroscience, health monitoring, diagnostics, and therapeutics. Recent major efforts focus on investigating strategies to fabricate flexible, stretchable, and soft electronic devices, and advances in materials chemistry have emerged as fundamental to the creation of the next generation of bioelectronics. This review summarizes contemporary advances and forthcoming technical challenges related to three principal components of bioelectronic devices: i) substrates and structural materials, ii) barrier and encapsulation materials, and iii) conductive materials. Through notable illustrations from the literature, integration and device fabrication strategies and associated challenges for each material class are highlighted.
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Affiliation(s)
| | - Jiwoo Song
- Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA
| | - Chenchen Mou
- Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA
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Vėbraitė I, Hanein Y. Soft Devices for High-Resolution Neuro-Stimulation: The Interplay Between Low-Rigidity and Resolution. FRONTIERS IN MEDICAL TECHNOLOGY 2022; 3:675744. [PMID: 35047928 PMCID: PMC8757739 DOI: 10.3389/fmedt.2021.675744] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/14/2021] [Indexed: 12/27/2022] Open
Abstract
The field of neurostimulation has evolved over the last few decades from a crude, low-resolution approach to a highly sophisticated methodology entailing the use of state-of-the-art technologies. Neurostimulation has been tested for a growing number of neurological applications, demonstrating great promise and attracting growing attention in both academia and industry. Despite tremendous progress, long-term stability of the implants, their large dimensions, their rigidity and the methods of their introduction and anchoring to sensitive neural tissue remain challenging. The purpose of this review is to provide a concise introduction to the field of high-resolution neurostimulation from a technological perspective and to focus on opportunities stemming from developments in materials sciences and engineering to reduce device rigidity while optimizing electrode small dimensions. We discuss how these factors may contribute to smaller, lighter, softer and higher electrode density devices.
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Affiliation(s)
- Ieva Vėbraitė
- School of Electrical Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Yael Hanein
- School of Electrical Engineering, Tel Aviv University, Tel Aviv, Israel
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Duy LT, Kang H, Shin HC, Han S, Singh R, Seo H. Multifunctional Nanohybrid of Alumina and Indium Oxide Prepared Using the Atomic Layer Deposition Technique. ACS APPLIED MATERIALS & INTERFACES 2021; 13:59115-59125. [PMID: 34860496 DOI: 10.1021/acsami.1c18623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Developing new transparent conducting materials, especially those having flexibility, is of great interest for electronic applications. Here, our study on using the ozone-assisted atomic layer deposition (ALD) technique at a low temperature of 200 °C for making an ultrathin, transparent, flexible, and highly electroconducting nanohybrid of indium and aluminum oxides is introduced. Through various characterizations, measurements, and density functional theory-based calculations, excellent electrical conductivity (∼950 S cm-1), transparency (95% in the visible region), and flexibility (bendable angle of 130° for 10 000 cycles) of our nanohybrid oxide thin film with a total layer thickness below 15 nm (2-4 nm for alumina and 10 nm for indium oxide) have been revealed and discussed. Besides, potential sensing applications of our oxide films on a flexible substrate have been demonstrated, such as strain sensors, temperature sensors (25-100 °C, resolution of 0.1 °C), and NO2 gas sensors (0.35-3.5 ppm, optimum operation at 65-75 °C). With the great potential in not only transparent conducting oxide but also sensing applications, our multifunctional nanohybrid prepared using a simple ozone-assisted ALD route opens more room for the applicability of transparent and flexible electronics.
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Affiliation(s)
- Le Thai Duy
- Department of Materials Science and Engineering, Ajou University, Suwon 16499, Republic of Korea
| | - Hyunwoo Kang
- Department of Energy Systems Research, Ajou University, Suwon 16499, Republic of Korea
| | - Hee-Cheol Shin
- Department of Energy Systems Research, Ajou University, Suwon 16499, Republic of Korea
| | - Seunggik Han
- Department of Materials Science and Engineering, Ajou University, Suwon 16499, Republic of Korea
| | - Ranveer Singh
- Department of Materials Science and Engineering, Ajou University, Suwon 16499, Republic of Korea
| | - Hyungtak Seo
- Department of Materials Science and Engineering, Ajou University, Suwon 16499, Republic of Korea
- Department of Energy Systems Research, Ajou University, Suwon 16499, Republic of Korea
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Monney B, Hess-Dunning AE, Gloth P, Capadona JR, Weder C. Mechanically adaptive implants fabricated with poly(2-hydroxyethyl methacrylate)-based negative photoresists. J Mater Chem B 2021; 8:6357-6365. [PMID: 32555874 DOI: 10.1039/d0tb00980f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Neural implants that are based on mechanically adaptive polymers (MAPs) and soften upon insertion into the body have previously been demonstrated to elicit a reduced chronic tissue response than more rigid devices fabricated from silicon or metals, but their processability has been limited. Here we report a negative photoresist approach towards physiologically responsive MAPs. We exploited this framework to create cross-linked terpolymers of 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate and 2-ethylhexyl methacrylate by photolithographic processes. Our systematic investigation of this platform afforded an optimized composition that exhibits a storage modulus E' of 1.8 GPa in the dry state. Upon exposure to simulated physiological conditions the material swells slightly (21% w/w) leading to a reduction of E' to 2 MPa. The large modulus change is mainly caused by plasticization, which shifts the glass transition from above to below 37 °C. Single shank probes fabricated by photolithography could readily be implanted into a brain-mimicking gel without buckling and viability studies with microglial cells show that the materials display excellent biocompatibility.
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Affiliation(s)
- Baptiste Monney
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700 Fribourg, Switzerland.
| | - Allison E Hess-Dunning
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH 44106, USA and Department of Biomedical Engineering, Case Western Reserve University, 2071 Martin Luther King Jr. Drive, Cleveland, OH 44106, USA
| | - Paul Gloth
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH 44106, USA and Department of Biomedical Engineering, Case Western Reserve University, 2071 Martin Luther King Jr. Drive, Cleveland, OH 44106, USA
| | - Jeffrey R Capadona
- Advanced Platform Technology Center, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH 44106, USA and Department of Biomedical Engineering, Case Western Reserve University, 2071 Martin Luther King Jr. Drive, Cleveland, OH 44106, USA
| | - Christoph Weder
- Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700 Fribourg, Switzerland.
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Hu P, Rooholghodos SA, Pham LH, Ly KL, Luo X. Interfacial Electrofabrication of Freestanding Biopolymer Membranes with Distal Electrodes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:11034-11043. [PMID: 32885979 PMCID: PMC8375314 DOI: 10.1021/acs.langmuir.0c01894] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Using electrical signals to guide materials' deposition has a long-standing history in metal coating, microchip fabrication, and the integration of organics with devices. In electrodeposition, however, the conductive materials can be deposited only onto the electrode surfaces. Here, an innovative process is presented to electrofabricate freestanding biopolymer membranes at the interface of electrolytes without any supporting electrodes at the fabrication site. Chitosan, a derivative from the naturally abundant biopolymer chitin, has been broadly explored in electrodeposition for integrating biological entities onto microfabricated devices. It is widely believed that the pH gradients generated at the cathode deprotonate the positively charged chitosan chains into a film on the cathode surface. The interfacial electrofabrication with pH indicators, however, demonstrated that the membrane growth was driven by the instantaneous flow of hydroxyl ions from the ambient alginate solution, rather than the slow propagation of pH gradients from the cathode surface. This interfacial electrofabrication produces freestanding membrane structures and can be expanded to other materials, which presents a new direction in using electrical signals for manufacturing.
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Konuray O, Fernández-Francos X, De la Flor S, Ramis X, Serra À. The Use of Click-Type Reactions in the Preparation of Thermosets. Polymers (Basel) 2020; 12:E1084. [PMID: 32397509 PMCID: PMC7285069 DOI: 10.3390/polym12051084] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 05/05/2020] [Accepted: 05/06/2020] [Indexed: 12/31/2022] Open
Abstract
Click chemistry has emerged as an effective polymerization method to obtain thermosets with enhanced properties for advanced applications. In this article, commonly used click reactions have been reviewed, highlighting their advantages in obtaining homogeneous polymer networks. The basic concepts necessary to understand network formation via click reactions, together with their main characteristics, are explained comprehensively. Some of the advanced applications of thermosets obtained by this methodology are also reviewed.
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Affiliation(s)
- Osman Konuray
- Thermodynamics Laboratory, ETSEIB Universitat Politècnica de Catalunya, Av. Diagonal 647, 08028 Barcelona, Spain; (O.K.); (X.F.-F.); (X.R.)
| | - Xavier Fernández-Francos
- Thermodynamics Laboratory, ETSEIB Universitat Politècnica de Catalunya, Av. Diagonal 647, 08028 Barcelona, Spain; (O.K.); (X.F.-F.); (X.R.)
| | - Silvia De la Flor
- Department of Mechanical Engineering, Universitat Rovira i Virgili, Av. Països Catalans 26, 43007 Tarragona, Spain;
| | - Xavier Ramis
- Thermodynamics Laboratory, ETSEIB Universitat Politècnica de Catalunya, Av. Diagonal 647, 08028 Barcelona, Spain; (O.K.); (X.F.-F.); (X.R.)
| | - Àngels Serra
- Department of Analytical and Organic Chemistry, University Rovira i Virgili, c/ Marcel·lí Domingo 1, 43007 Tarragona, Spain
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Márton G, Tóth EZ, Wittner L, Fiáth R, Pinke D, Orbán G, Meszéna D, Pál I, Győri EL, Bereczki Z, Kandrács Á, Hofer KT, Pongrácz A, Ulbert I, Tóth K. The neural tissue around SU-8 implants: A quantitative in vivo biocompatibility study. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2020; 112:110870. [PMID: 32409039 DOI: 10.1016/j.msec.2020.110870] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 02/26/2020] [Accepted: 03/19/2020] [Indexed: 12/30/2022]
Abstract
The use of SU-8 material in the production of neural sensors has grown recently. Despite its widespread application, a detailed systematic quantitative analysis concerning its biocompatibility in the central nervous system is lacking. In this immunohistochemical study, we quantified the neuronal preservation and the severity of astrogliosis around SU-8 devices implanted in the neocortex of rats, after a 2 months survival. We found that the density of neurons significantly decreased up to a distance of 20 μm from the implant, with an averaged density decrease to 24 ± 28% of the control. At 20 to 40 μm distance from the implant, the majority of the neurons was preserved (74 ± 39% of the control) and starting from 40 μm distance from the implant, the neuron density was control-like. The density of synaptic contacts - examined at the electron microscopic level - decreased in the close vicinity of the implant, but it recovered to the control level as close as 24 μm from the implant track. The intensity of the astroglial staining significantly increased compared to the control region, up to 560 μm and 480 μm distance from the track in the superficial and deep layers of the neocortex, respectively. Electron microscopic examination revealed that the thickness of the glial scar was around 5-10 μm thin, and the ratio of glial processes in the neuropil was not more than 16% up to a distance of 12 μm from the implant. Our data suggest that neuronal survival is affected only in a very small area around the implant. The glial scar surrounding the implant is thin, and the presence of glial elements is low in the neuropil, although the signs of astrogliosis could be observed up to about 500 μm from the track. Subsequently, the biocompatibility of the SU-8 material is high. Due to its low cost fabrication and more flexible nature, SU-8 based devices may offer a promising approach to experimental and clinical applications in the future.
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Affiliation(s)
- Gergely Márton
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter utca 50/A, Budapest 1083, Hungary; Doctoral School on Materials Sciences and Technologies, Óbuda University, Bécsi út 96/b, Budapest 1034, Hungary.
| | - Estilla Zsófia Tóth
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary; János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Üllői út 26, Budapest 1085, Hungary.
| | - Lucia Wittner
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter utca 50/A, Budapest 1083, Hungary; National Institute of Clinical Neuroscience, Amerikai út 57, Budapest, Hungary, 1145.
| | - Richárd Fiáth
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter utca 50/A, Budapest 1083, Hungary.
| | - Domonkos Pinke
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter utca 50/A, Budapest 1083, Hungary.
| | - Gábor Orbán
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary; Doctoral School on Materials Sciences and Technologies, Óbuda University, Bécsi út 96/b, Budapest 1034, Hungary.
| | - Domokos Meszéna
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter utca 50/A, Budapest 1083, Hungary.
| | - Ildikó Pál
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary.
| | - Edit Lelle Győri
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter utca 50/A, Budapest 1083, Hungary; National Institute of Clinical Neuroscience, Amerikai út 57, Budapest, Hungary, 1145
| | - Zsófia Bereczki
- Department of Control Engineering and Information Technology, Budapest University of Technology and Economics, Magyar tudósok körútja 2, Budapest 1117, Hungary
| | - Ágnes Kandrács
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter utca 50/A, Budapest 1083, Hungary.
| | - Katharina T Hofer
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter utca 50/A, Budapest 1083, Hungary.
| | - Anita Pongrácz
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter utca 50/A, Budapest 1083, Hungary; Institute of Technical Physics and Materials Science, Centre for Energy Research, Konkoly Thege Miklós út 29-33, Budapest 1121, Hungary.
| | - István Ulbert
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter utca 50/A, Budapest 1083, Hungary; National Institute of Clinical Neuroscience, Amerikai út 57, Budapest, Hungary, 1145.
| | - Kinga Tóth
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest 1117, Hungary.
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Monney B, Dibble AG, Moatsou D, Weder C. Highly Cross-Linked, Physiologically Responsive, Mechanically Adaptive Polymer Networks Made by Photopolymerization. ACS OMEGA 2020; 5:3090-3097. [PMID: 32095732 PMCID: PMC7034001 DOI: 10.1021/acsomega.9b04336] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 01/24/2020] [Indexed: 06/10/2023]
Abstract
Mechanically adaptive materials that soften upon exposure to physiological conditions are useful for biomedical applications, notably as substrates for implantable neural electrodes. So far, device fabrication efforts have largely relied on shaping such devices by laser cutting, but this process makes it difficult to produce complex electrode architectures and leads to ill-defined surface chemistries. Here, we report mechanically adaptive, physiologically responsive polymers that can be photopolymerized and thus patterned via soft lithography and photolithography. The adaptive polymer networks produced exhibit, in optimized compositions, a ca. 500-fold decrease of their storage modulus when exposed to simulated physiological conditions, for example, from 2.5 GPa to 5 MPa. This effect is caused by modest swelling (30% w/w), which in turn leads to plasticization so that the polymer network's glass transition temperature is reduced from 145 to 25 °C. The polymer networks can further be rendered pH-responsive by the incorporation of methacrylic acid. The dual stimuli-responsive materials thus made show promise as coatings or substrates for drug delivery devices.
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Affiliation(s)
| | | | - Dafni Moatsou
- E-mail: . Current address: Karlsruher Institut
für Technologie, Institut
für Organische Chemie, Fritz-Haber-Weg 6, 76131 Karlsruhe,
Germany (D.M.)
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Kim T, Schmidt K, Deemie C, Wycech J, Liang H, Giszter SF. Highly Flexible Precisely Braided Multielectrode Probes and Combinatorics for Future Neuroprostheses. Front Neurosci 2019; 13:613. [PMID: 31275102 PMCID: PMC6591490 DOI: 10.3389/fnins.2019.00613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Accepted: 05/28/2019] [Indexed: 11/13/2022] Open
Abstract
The braided multielectrode probe (BMEP) is an ultrafine microwire bundle interwoven into a precise tubular braided structure, which is designed to be used as an invasive neural probe consisting of multiple microelectrodes for electrophysiological neural recording and stimulation. Significant advantages of BMEPs include highly flexible mechanical properties leading to decreased immune responses after chronic implantation in neural tissue and dense recording/stimulation sites (24 channels) within the 100-200 μm diameter. In addition, because BMEPs can be manufactured using various materials in any size and shape without length limitations, they could be expanded to applications in deep central nervous system (CNS) regions as well as peripheral nervous system (PNS) in larger animals and humans. Finally, the 3D topology of wires supports combinatoric rearrangements of wires within braids, and potential neural yield increases. With the newly developed next generation micro braiding machine, we can manufacture more precise and complex microbraid structures. In this article, we describe the new machine and methods, and tests of simulated combinatoric separation methods. We propose various promising BMEP designs and the potential modifications to these designs to create probes suitable for various applications for future neuroprostheses.
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Affiliation(s)
- Taegyo Kim
- Neurobiology and Anatomy Department, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Kendall Schmidt
- Neurobiology and Anatomy Department, Drexel University College of Medicine, Philadelphia, PA, United States
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
| | - Christopher Deemie
- Neurobiology and Anatomy Department, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Joanna Wycech
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
| | - Hualou Liang
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
| | - Simon F. Giszter
- Neurobiology and Anatomy Department, Drexel University College of Medicine, Philadelphia, PA, United States
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, United States
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Ecker M, Joshi-Imre A, Modi R, Frewin CL, Garcia-Sandoval A, Maeng J, Gutierrez-Heredia G, Pancrazio JJ, Voit WE. From softening polymers to multimaterial based bioelectronic devices. ACTA ACUST UNITED AC 2018. [DOI: 10.1088/2399-7532/aaed58] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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12
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Hess-Dunning A, Tyler DJ. A Mechanically-Adaptive Polymer Nanocomposite-Based Intracortical Probe and Package for Chronic Neural Recording. MICROMACHINES 2018; 9:E583. [PMID: 30413034 PMCID: PMC6265703 DOI: 10.3390/mi9110583] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 10/19/2018] [Accepted: 11/02/2018] [Indexed: 12/23/2022]
Abstract
Mechanical, materials, and biological causes of intracortical probe failure have hampered their utility in basic science and clinical applications. By anticipating causes of failure, we can design a system that will prevent the known causes of failure. The neural probe design was centered around a bio-inspired, mechanically-softening polymer nanocomposite. The polymer nanocomposite was functionalized with recording microelectrodes using a microfabrication process designed for chemical and thermal process compatibility. A custom package based upon a ribbon cable, printed circuit board, and a 3D-printed housing was designed to enable connection to external electronics. Probes were implanted into the primary motor cortex of Sprague-Dawley rats for 16 weeks, during which regular recording and electrochemical impedance spectroscopy measurement sessions took place. The implanted mechanically-softening probes had stable electrochemical impedance spectra across the 16 weeks and single units were recorded out to 16 weeks. The demonstration of chronic neural recording with the mechanically-softening probe suggests that probe architecture, custom package, and general design strategy are appropriate for long-term studies in rodents.
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Affiliation(s)
- Allison Hess-Dunning
- Rehabilitation Research and Development, Louis Stokes Cleveland VA Medical Center, Cleveland, OH 44106, USA.
- Advanced Platform Technology Center, Cleveland, OH 44106, USA.
| | - Dustin J Tyler
- Rehabilitation Research and Development, Louis Stokes Cleveland VA Medical Center, Cleveland, OH 44106, USA.
- Advanced Platform Technology Center, Cleveland, OH 44106, USA.
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA.
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González-González MA, Kanneganti A, Joshi-Imre A, Hernandez-Reynoso AG, Bendale G, Modi R, Ecker M, Khurram A, Cogan SF, Voit WE, Romero-Ortega MI. Thin Film Multi-Electrode Softening Cuffs for Selective Neuromodulation. Sci Rep 2018; 8:16390. [PMID: 30401906 PMCID: PMC6219541 DOI: 10.1038/s41598-018-34566-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 10/18/2018] [Indexed: 01/21/2023] Open
Abstract
Silicone nerve cuff electrodes are commonly implanted on relatively large and accessible somatic nerves as peripheral neural interfaces. While these cuff electrodes are soft (1–50 MPa), their self-closing mechanism requires of thick walls (200–600 µm), which in turn contribute to fibrotic tissue growth around and inside the device, compromising the neural interface. We report the use of thiol-ene/acrylate shape memory polymer (SMP) for the fabrication of thin film multi-electrode softening cuffs (MSC). We fabricated multi-size MSC with eight titanium nitride (TiN) electrodes ranging from 1.35 to 13.95 × 10−4 cm2 (1–3 kΩ) and eight smaller gold (Au) electrodes (3.3 × 10−5 cm2; 750 kΩ), that soften at physiological conditions to a modulus of 550 MPa. While the SMP material is not as soft as silicone, the flexural forces of the SMP cuff are about 70–700 times lower in the MSC devices due to the 30 μm thick film compared to the 600 μm thick walls of the silicone cuffs. We demonstrated the efficacy of the MSC to record neural signals from rat sciatic and pelvic nerves (1000 µm and 200 µm diameter, respectively), and the selective fascicular stimulation by current steering. When implanted side-by-side and histologically compared 30 days thereafter, the MSC devices showed significantly less inflammation, indicated by a 70–80% reduction in ED1 positive macrophages, and 54–56% less fibrotic vimentin immunoreactivity. Together, the data supports the use of MSC as compliant and adaptable technology for the interfacing of somatic and autonomic peripheral nerves.
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Affiliation(s)
- María A González-González
- Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
| | - Aswini Kanneganti
- Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
| | - Alexandra Joshi-Imre
- Department of Material Science and Engineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
| | - Ana G Hernandez-Reynoso
- Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
| | - Geetanjali Bendale
- Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
| | - Romil Modi
- Department of Material Science and Engineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
| | - Melanie Ecker
- Department of Material Science and Engineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
| | - Ali Khurram
- Department of Material Science and Engineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
| | - Stuart F Cogan
- Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
| | - Walter E Voit
- Department of Material Science and Engineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA
| | - Mario I Romero-Ortega
- Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Road, Richardson, TX, 75080, USA.
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14
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Black BJ, Ecker M, Stiller A, Rihani R, Danda VR, Reed I, Voit WE, Pancrazio JJ. In vitro compatibility testing of thiol-ene/acrylate-based shape memory polymers for use in implantable neural interfaces. J Biomed Mater Res A 2018; 106:2891-2898. [PMID: 30371968 DOI: 10.1002/jbm.a.36478] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 05/06/2018] [Accepted: 05/24/2018] [Indexed: 12/26/2022]
Abstract
Shape memory polymers (SMPs) based on thiol-ene/acrylate formulations are an emerging class of materials with potential applications as structural and/or dielectric coatings for implantable neural interfaces. Here, we report in vitro compatibility studies of three novel thiol-ene/acrylate-based SMP formulations. In vivo cytotoxicity assays were carried out in accordance with International Organization for Standards (ISO) protocol 10993-5, using NCTC clone 929 fibroblasts as well as embryonic cortical cultures. All three SMP formulations passed standardized cytotoxicity assays (>70% normalized cell viability) using both cell types. Functional neurotoxicity assays were carried out using primary cortical networks cultured on substrate-integrated microelectrode arrays (MEAs). We observed significant reduction in cortical network activity in the case of positive control material, but no significant alterations in activity following incubation with SMP material extracts, indicating functional cytocompatibility. Finally, we assessed cell reactivity at the tissue-material interface by performing an in vitro glial scarring assay. Through immunostaining, we observed similar astrocyte-associated (GFAP) mean intensity ratios near nonsoftening SMP-coated and uncoated stainless steel microwires (1.10 ± 0.06 vs. 1.19 ± 0.10), suggesting similar glial cell reactivity. However, we observed decreased mean intensity ratios in the presence of fully softening SMP-coated microwires (1.02 ± 0.04) suggesting reduced glial cell reactivity. Overall, these results indicate that the thiol-ene/acrylate SMP formulations presented here are neither cytotoxic nor neurotoxic, and suggest that fully softening SMP may reduce foreign body response in terms of glial cell reactivity. These findings support further consideration of this class of materials as backbone or insulating materials for implantable neural stimulating/recording devices. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2891-2898, 2018.
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Affiliation(s)
- Bryan J Black
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Bioengineering and Sciences Building 13.633, Richardson, Texas, 75080
| | - Melanie Ecker
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Bioengineering and Sciences Building 13.633, Richardson, Texas, 75080
| | - Allison Stiller
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Bioengineering and Sciences Building 13.633, Richardson, Texas, 75080
| | - Rashed Rihani
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Bioengineering and Sciences Building 13.633, Richardson, Texas, 75080
| | - Vindhya Reddy Danda
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Bioengineering and Sciences Building 13.633, Richardson, Texas, 75080
| | - Isabella Reed
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Bioengineering and Sciences Building 13.633, Richardson, Texas, 75080
| | - Walter E Voit
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Bioengineering and Sciences Building 13.633, Richardson, Texas, 75080
| | - Joseph J Pancrazio
- Department of Bioengineering, The University of Texas at Dallas, 800 W. Campbell Road, Bioengineering and Sciences Building 13.633, Richardson, Texas, 75080
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15
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Mehrali M, Bagherifard S, Akbari M, Thakur A, Mirani B, Mehrali M, Hasany M, Orive G, Das P, Emneus J, Andresen TL, Dolatshahi‐Pirouz A. Blending Electronics with the Human Body: A Pathway toward a Cybernetic Future. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2018; 5:1700931. [PMID: 30356969 PMCID: PMC6193179 DOI: 10.1002/advs.201700931] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 05/24/2018] [Indexed: 05/22/2023]
Abstract
At the crossroads of chemistry, electronics, mechanical engineering, polymer science, biology, tissue engineering, computer science, and materials science, electrical devices are currently being engineered that blend directly within organs and tissues. These sophisticated devices are mediators, recorders, and stimulators of electricity with the capacity to monitor important electrophysiological events, replace disabled body parts, or even stimulate tissues to overcome their current limitations. They are therefore capable of leading humanity forward into the age of cyborgs, a time in which human biology can be hacked at will to yield beings with abilities beyond their natural capabilities. The resulting advances have been made possible by the emergence of conformal and soft electronic materials that can readily integrate with the curvilinear, dynamic, delicate, and flexible human body. This article discusses the recent rapid pace of development in the field of cybernetics with special emphasis on the important role that flexible and electrically active materials have played therein.
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Affiliation(s)
- Mehdi Mehrali
- Technical University of DenmarkDTU NanotechCenter for Nanomedicine and Theranostics2800KgsDenmark
| | - Sara Bagherifard
- Department of Mechanical EngineeringPolitecnico di Milano20156MilanItaly
| | - Mohsen Akbari
- Laboratory for Innovations in MicroEngineering (LiME)Department of Mechanical EngineeringUniversity of VictoriaVictoriaBCV8P 5C2Canada
- Center for Biomedical ResearchUniversity of VictoriaVictoriaV8P 5C2Canada
- Center for Advanced Materials and Related Technologies (CAMTEC)University of VictoriaVictoriaV8P 5C2Canada
| | - Ashish Thakur
- Technical University of DenmarkDTU NanotechCenter for Nanomedicine and Theranostics2800KgsDenmark
| | - Bahram Mirani
- Laboratory for Innovations in MicroEngineering (LiME)Department of Mechanical EngineeringUniversity of VictoriaVictoriaBCV8P 5C2Canada
- Center for Biomedical ResearchUniversity of VictoriaVictoriaV8P 5C2Canada
- Center for Advanced Materials and Related Technologies (CAMTEC)University of VictoriaVictoriaV8P 5C2Canada
| | - Mohammad Mehrali
- Process and Energy DepartmentDelft University of TechnologyLeeghwaterstraat 392628CBDelftThe Netherlands
| | - Masoud Hasany
- Technical University of DenmarkDTU NanotechCenter for Nanomedicine and Theranostics2800KgsDenmark
| | - Gorka Orive
- NanoBioCel GroupLaboratory of PharmaceuticsSchool of PharmacyUniversity of the Basque Country UPV/EHUPaseo de la Universidad 701006Vitoria‐GasteizSpain
- Biomedical Research Networking Centre in Bioengineering, Biomaterials, and Nanomedicine (CIBER‐BBN)Vitoria‐Gasteiz28029Spain
- University Institute for Regenerative Medicine and Oral Implantology—UIRMI (UPV/EHU‐Fundación Eduardo Anitua)Vitoria01007Spain
| | - Paramita Das
- School of Chemical and Biomedical EngineeringNanyang Technological University62 Nanyang DriveSingapore637459Singapore
| | - Jenny Emneus
- Technical University of DenmarkDTU Nanotech2800KgsDenmark
| | - Thomas L. Andresen
- Technical University of DenmarkDTU NanotechCenter for Nanomedicine and Theranostics2800KgsDenmark
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16
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Mah AH, Mei H, Basu P, Laws TS, Ruchhoeft P, Verduzco R, Stein GE. Swelling responses of surface-attached bottlebrush polymer networks. SOFT MATTER 2018; 14:6728-6736. [PMID: 30062351 DOI: 10.1039/c8sm01127c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The swelling responses of thin polymer networks were examined as a function of primary polymer architecture. Thin films of linear or bottlebrush polystyrene were cast on polystyrene-grafted substrates, and surface-attached networks were prepared with a radiation crosslinking reaction. The dry and equilibrated swollen thicknesses were both determined with spectroscopic ellipsometry. The dry thickness, which reflects the insoluble fraction of the film after crosslinking, depends on the primary polymer size and radiation dose but is largely independent of primary polymer architecture. When networks are synthesized with a high radiation dose, producing a high density of crosslinks, the extent of swelling is similar for all primary polymer architectures and molecular weights. However, when networks are synthesized with a low radiation dose, the extent of swelling is reduced as the primary polymer becomes larger or increasingly branched. These trends are consistent with a simple Flory model for equilibrium swelling that describes the effects of branch junctions and radiation crosslinks on network elasticity.
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Affiliation(s)
- Adeline Huizhen Mah
- Materials Science and Engineering Program, University of Houston, Houston, TX 77204, USA
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17
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Prospects for a Robust Cortical Recording Interface. Neuromodulation 2018. [DOI: 10.1016/b978-0-12-805353-9.00028-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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18
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Review of Recent Inkjet-Printed Capacitive Tactile Sensors. SENSORS 2017; 17:s17112593. [PMID: 29125584 PMCID: PMC5713153 DOI: 10.3390/s17112593] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 10/20/2017] [Accepted: 11/07/2017] [Indexed: 11/17/2022]
Abstract
Inkjet printing is an advanced printing technology that has been used to develop conducting layers, interconnects and other features on a variety of substrates. It is an additive manufacturing process that offers cost-effective, lightweight designs and simplifies the fabrication process with little effort. There is hardly sufficient research on tactile sensors and inkjet printing. Advancements in materials science and inkjet printing greatly facilitate the realization of sophisticated tactile sensors. Starting from the concept of capacitive sensing, a brief comparison of printing techniques, the essential requirements of inkjet-printing and the attractive features of state-of-the art inkjet-printed tactile sensors developed on diverse substrates (paper, polymer, glass and textile) are presented in this comprehensive review. Recent trends in inkjet-printed wearable/flexible and foldable tactile sensors are evaluated, paving the way for future research.
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19
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Do DH, Ecker M, Voit WE. Characterization of a Thiol-Ene/Acrylate-Based Polymer for Neuroprosthetic Implants. ACS OMEGA 2017; 2:4604-4611. [PMID: 30023725 PMCID: PMC6044618 DOI: 10.1021/acsomega.7b00834] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 08/04/2017] [Indexed: 05/18/2023]
Abstract
Thiol-ene/acrylate shape-memory polymers can be used as base substrates for neural electrodes to treat neurological dysfunction. Neural electrodes are implanted into the body to alter or record impulse conduction. This study characterizes thiol-ene/acrylate polymers to determine which synthesis methods constitute an ideal substrate for neural implants. To achieve a desired Tg between 50 and 56.5 °C, curing conditions, polymer thickness, monomer ratios, and water uptake were all examined and controlled for. Characterization with dynamic mechanical analysis and thermal gravimetric analysis reveals that thin, thiol-ene/acrylate polymers composed of at least 50 mol % acrylate content and cured for at least 1 h at 365 nm are promising as substrates for neural electrodes.
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Affiliation(s)
- Dang-Huy Do
- Department
of Biological Sciences and Department of Materials Science
and Engineering, The University of Texas
at Dallas, 800 W Campbell Road, Richardson, Texas 75080, United
States
| | - Melanie Ecker
- Department
of Biological Sciences and Department of Materials Science
and Engineering, The University of Texas
at Dallas, 800 W Campbell Road, Richardson, Texas 75080, United
States
| | - Walter E. Voit
- Department
of Biological Sciences and Department of Materials Science
and Engineering, The University of Texas
at Dallas, 800 W Campbell Road, Richardson, Texas 75080, United
States
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20
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Wang W, Salazar J, Vahabi H, Joshi-Imre A, Voit WE, Kota AK. Metamorphic Superomniphobic Surfaces. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1700295. [PMID: 28485512 DOI: 10.1002/adma.201700295] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 03/19/2017] [Indexed: 06/07/2023]
Abstract
Superomniphobic surfaces are extremely repellent to virtually all liquids. By combining superomniphobicity and shape memory effect, metamorphic superomniphobic (MorphS) surfaces that transform their morphology in response to heat are developed. Utilizing the MorphS surfaces, the distinctly different wetting transitions of liquids with different surface tensions are demonstrated and the underlying physics is elucidated. Both ex situ and in situ wetting transitions on the MorphS surfaces are solely due to transformations in morphology of the surface texture. It is envisioned that the robust MorphS surfaces with reversible wetting transition will have a wide range of applications including rewritable liquid patterns, controlled drug release systems, lab-on-a-chip devices, and biosensors.
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Affiliation(s)
- Wei Wang
- Department of Mechanical Engineering, Colorado State University, Fort Collins, CO, 80523, USA
| | - Joshua Salazar
- Department of Mechanical Engineering, The University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Hamed Vahabi
- Department of Mechanical Engineering, Colorado State University, Fort Collins, CO, 80523, USA
| | - Alexandra Joshi-Imre
- Center for Engineering Innovation, The University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Walter E Voit
- Department of Materials Science, Department of Mechanical Engineering, Department of Bioengineering, Department of Chemistry, The University of Texas at Dallas, Richardson, TX, 75080, USA
| | - Arun K Kota
- Department of Mechanical Engineering, School of Biomedical Engineering, Colorado State University, Fort Collins, CO, 80523, USA
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21
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Parker S, Reit R, Abitz H, Ellson G, Yang K, Lund B, Voit WE. High-Tg Thiol-Click Thermoset Networks via the Thiol-Maleimide Michael Addition. Macromol Rapid Commun 2016; 37:1027-32. [PMID: 27168131 DOI: 10.1002/marc.201600033] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 03/09/2016] [Indexed: 11/12/2022]
Abstract
Thiol-click reactions lead to polymeric materials with a wide range of interesting mechanical, electrical, and optical properties. However, this reaction mechanism typically results in bulk materials with a low glass transition temperature (Tg ) due to rotational flexibility around the thioether linkages found in networks such as thiol-ene, thiol-epoxy, and thiol-acrylate systems. This report explores the thiol-maleimide reaction utilized for the first time as a solvent-free reaction system to synthesize high-Tg thermosetting networks. Through thermomechanical characterization via dynamic mechanical analysis, the homogeneity and Tg s of thiol-maleimide networks are compared to similarly structured thiol-ene and thiol-epoxy networks. While preliminary data show more heterogeneous networks for thiol-maleimide systems, bulk materials exhibit Tg s 80 °C higher than other thiol-click systems explored herein. Finally, hollow tubes are synthesized using each thiol-click reaction mechanism and employed in low- and high-temperature environments, demonstrating the ability to withstand a compressive radial 100 N deformation at 100 °C wherein other thiol-click systems fail mechanically.
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Affiliation(s)
- Shelbi Parker
- Department of Bioengineering, The University of Texas at Dallas, 800 West Campbell Road, Mailstop RL 10, Richardson, TX, 75080, USA
| | - Radu Reit
- Department of Bioengineering, The University of Texas at Dallas, 800 West Campbell Road, Mailstop RL 10, Richardson, TX, 75080, USA
| | - Haley Abitz
- Department of Mechanical Engineering, The University of Texas at Dallas, 800 West Campbell Road, Mailstop RL 10, Richardson, TX, 75080, USA
| | - Gregory Ellson
- Department of Materials Science and Engineering, The University of Texas at Dallas, 800 West Campbell Road, Mailstop RL 10, Richardson, TX, 75080, USA
| | - Kejia Yang
- Department of Chemistry, The University of Texas at Dallas, 800 West Campbell Road, Mailstop RL 10, Richardson, TX, 75080, USA
| | - Benjamin Lund
- Department of Materials Science and Engineering, The University of Texas at Dallas, 800 West Campbell Road, Mailstop RL 10, Richardson, TX, 75080, USA
| | - Walter E Voit
- Department of Bioengineering, The University of Texas at Dallas, 800 West Campbell Road, Mailstop RL 10, Richardson, TX, 75080, USA.,Department of Mechanical Engineering, The University of Texas at Dallas, 800 West Campbell Road, Mailstop RL 10, Richardson, TX, 75080, USA.,Department of Materials Science and Engineering, The University of Texas at Dallas, 800 West Campbell Road, Mailstop RL 10, Richardson, TX, 75080, USA.,Department of Chemistry, The University of Texas at Dallas, 800 West Campbell Road, Mailstop RL 10, Richardson, TX, 75080, USA
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22
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Reit R, Zamorano D, Parker S, Simon D, Lund B, Voit W, Ware TH. Hydrolytically Stable Thiol-ene Networks for Flexible Bioelectronics. ACS APPLIED MATERIALS & INTERFACES 2015; 7:28673-28681. [PMID: 26650346 DOI: 10.1021/acsami.5b10593] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Hydrolytically stable, tunable modulus polymer networks are demonstrated to survive harsh alkaline environments and offer promise for use in long-term implantable bioelectronic medicines known as electroceuticals. Today's polymer networks (such as polyimides or polysiloxanes) succeed in providing either stiff or soft substrates for bioelectronics devices; however, the capability to significantly tune the modulus of such materials is lacking. Within the space of materials with easily modified elastic moduli, thiol-ene copolymers are a subset of materials that offer a promising solution to build next generation flexible bioelectronics but have typically been susceptible to hydrolytic degradation chronically. In this inquiry, we demonstrate a materials space capable of tuning the substrate modulus and explore the mechanical behavior of such networks. Furthermore, we fabricate an array of microelectrodes that can withstand accelerated aging environments shown to destroy conventional flexible bioelectronics.
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Affiliation(s)
- Radu Reit
- Department of Bioengineering, ‡Department of Chemistry, §Department of Materials Science and Engineering, and ∥Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Mailstop RL 10, Richardson, Texas 75080, United States
| | - Daniel Zamorano
- Department of Bioengineering, ‡Department of Chemistry, §Department of Materials Science and Engineering, and ∥Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Mailstop RL 10, Richardson, Texas 75080, United States
| | - Shelbi Parker
- Department of Bioengineering, ‡Department of Chemistry, §Department of Materials Science and Engineering, and ∥Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Mailstop RL 10, Richardson, Texas 75080, United States
| | - Dustin Simon
- Department of Bioengineering, ‡Department of Chemistry, §Department of Materials Science and Engineering, and ∥Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Mailstop RL 10, Richardson, Texas 75080, United States
| | - Benjamin Lund
- Department of Bioengineering, ‡Department of Chemistry, §Department of Materials Science and Engineering, and ∥Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Mailstop RL 10, Richardson, Texas 75080, United States
| | - Walter Voit
- Department of Bioengineering, ‡Department of Chemistry, §Department of Materials Science and Engineering, and ∥Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Mailstop RL 10, Richardson, Texas 75080, United States
| | - Taylor H Ware
- Department of Bioengineering, ‡Department of Chemistry, §Department of Materials Science and Engineering, and ∥Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Mailstop RL 10, Richardson, Texas 75080, United States
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23
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Arreaga-Salas DE, Avendaño-Bolívar A, Simon D, Reit R, Garcia-Sandoval A, Rennaker RL, Voit W. Integration of High-Charge-Injection-Capacity Electrodes onto Polymer Softening Neural Interfaces. ACS APPLIED MATERIALS & INTERFACES 2015; 7:26614-23. [PMID: 26575084 DOI: 10.1021/acsami.5b08139] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Softening neural interfaces are implanted stiff to enable precise insertion, and they soften in physiological conditions to minimize modulus mismatch with tissue. In this work, a high-charge-injection-capacity iridium electrode fabrication process is detailed. For the first time, this process enables integration of iridium electrodes onto softening substrates using photolithography to define all features in the device. Importantly, no electroplated layers are utilized, leading to a highly scalable method for consistent device fabrication. The iridium electrode is metallically bonded to the gold conductor layer, which is covalently bonded to the softening substrate via sulfur-based click chemistry. The resulting shape-memory polymer neural interfaces can deliver more than 2 billion symmetric biphasic pulses (100 μs/phase), with a charge of 200 μC/cm(2) and geometric surface area (GSA) of 300 μm(2). A transfer-by-polymerization method is used in combination with standard semiconductor processing techniques to fabricate functional neural probes onto a thiol-ene-based, thin film substrate. Electrical stability is tested under simulated physiological conditions in an accelerated electrical aging paradigm with periodic measurement of electrochemical impedance spectra (EIS) and charge storage capacity (CSC) at various intervals. Electrochemical characterization and both optical and scanning electron microscopy suggest significant breakdown of the 600 nm-thick parylene-C insulation, although no delamination of the conductors or of the final electrode interface was observed. Minor cracking at the edges of the thin film iridium electrodes was occasionally observed. The resulting devices will provide electrical recording and stimulation of the nervous system to better understand neural wiring and timing, to target treatments for debilitating diseases, and to give neuroscientists spatially selective and specific tools to interact with the body. This approach has uses for cochlear implants, nerve cuff electrodes, penetrating cortical probes, spinal stimulators, blanket electrodes for the gut, stomach, and visceral organs and a host of other custom nerve-interfacing devices.
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Affiliation(s)
- David E Arreaga-Salas
- Department of Materials Science and Engineering, ‡Department of Bioengineering, and §Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Richardson, Texas 75080-3021, United States
| | - Adrian Avendaño-Bolívar
- Department of Materials Science and Engineering, ‡Department of Bioengineering, and §Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Richardson, Texas 75080-3021, United States
| | - Dustin Simon
- Department of Materials Science and Engineering, ‡Department of Bioengineering, and §Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Richardson, Texas 75080-3021, United States
| | - Radu Reit
- Department of Materials Science and Engineering, ‡Department of Bioengineering, and §Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Richardson, Texas 75080-3021, United States
| | - Aldo Garcia-Sandoval
- Department of Materials Science and Engineering, ‡Department of Bioengineering, and §Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Richardson, Texas 75080-3021, United States
| | - Robert L Rennaker
- Department of Materials Science and Engineering, ‡Department of Bioengineering, and §Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Richardson, Texas 75080-3021, United States
| | - Walter Voit
- Department of Materials Science and Engineering, ‡Department of Bioengineering, and §Department of Mechanical Engineering, The University of Texas at Dallas , 800 West Campbell Road, Richardson, Texas 75080-3021, United States
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24
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Kang DY, Kim YS, Ornelas G, Sinha M, Naidu K, Coleman TP. Scalable Microfabrication Procedures for Adhesive-Integrated Flexible and Stretchable Electronic Sensors. SENSORS 2015; 15:23459-76. [PMID: 26389915 PMCID: PMC4610501 DOI: 10.3390/s150923459] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/05/2015] [Accepted: 09/10/2015] [Indexed: 12/05/2022]
Abstract
New classes of ultrathin flexible and stretchable devices have changed the way modern electronics are designed to interact with their target systems. Though more and more novel technologies surface and steer the way we think about future electronics, there exists an unmet need in regards to optimizing the fabrication procedures for these devices so that large-scale industrial translation is realistic. This article presents an unconventional approach for facile microfabrication and processing of adhesive-peeled (AP) flexible sensors. By assembling AP sensors on a weakly-adhering substrate in an inverted fashion, we demonstrate a procedure with 50% reduced end-to-end processing time that achieves greater levels of fabrication yield. The methodology is used to demonstrate the fabrication of electrical and mechanical flexible and stretchable AP sensors that are peeled-off their carrier substrates by consumer adhesives. In using this approach, we outline the manner by which adhesion is maintained and buckling is reduced for gold film processing on polydimethylsiloxane substrates. In addition, we demonstrate the compatibility of our methodology with large-scale post-processing using a roll-to-roll approach.
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Affiliation(s)
- Dae Y Kang
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA.
| | - Yun-Soung Kim
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA.
| | - Gladys Ornelas
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA.
| | - Mridu Sinha
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA.
| | - Keerthiga Naidu
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA.
| | - Todd P Coleman
- Department of Bioengineering, University of California San Diego, La Jolla, CA 92093, USA.
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Abstract
PURPOSE Although a few techniques for lengthening intestine by mechanical stretch have been described, they are relatively complex, and the majority involve placement of an intraluminal device. Ideally, techniques applicable to humans would be easy to perform and extraluminal to avoid the potential for mucosal injury. This study of distraction enterogenesis used an extraluminal, radially self-expanding shape-memory polymer cylinder and a simple operative approach to both elongate intestine and grow new tissue. METHODS Young Sprague Dawley rats (250-350 g) underwent Roux-en-Y isolation of a small intestinal limb and were divided in three groups: no further manipulation (Control 1, C1); placement of a nonexpanding device (Control 2, C2); or placement of a radially expanding device by the limb (Experimental, Exp). For C2 and Exp animals, the blind end of the limb was wrapped around the radially expanding cylindrical device with the limb-end sutured back to the limb-side. Bowel length was measured at operation and at necropsy (14 days) both in-situ and ex-vivo under standard tension (6g weight). Change in length is shown as mean ± standard deviation. A blinded gastrointestinal pathologist reviewed histology and recorded multiple measures of intestinal adaptation. The DNA to protein ratio was quantified as a surrogate for cellular proliferation. Changes in length, histologic measures, and DNA:protein were compared using analysis of variance, with significance set at P<0.05. RESULTS The length of the Roux limb in situ increased significantly in Exp animals (n=8, 29.0 ± 5.8mm) compared with C1 animals (n=5, -11.2 ± 9.0mm, P<0.01). The length of the Roux limb ex vivo under standard tension increased in the Exp group (25.8 ± 4.2mm) compared with the C2 group (n=6, -4.3 ± 6.0, P<0.01). There were no differences in histologic measures of bowel adaptation between the groups, namely villous height and width, crypt depth, crypt density, and crypt fission rate (all P ≥ 0.08). Muscularis mucosal thickness was also not different (P=0.25). There was no difference in DNA:protein between groups (P=0.47). CONCLUSION An extraluminally placed, radially expanding shape-memory polymer cylinder successfully lengthened intestine, without damaging mucosa. Lack of difference in muscularis thickness and a constant DNA:protein ratio suggests that this process may be related to actual growth rather than mere stretch. This study demonstrated a simple approach that warrants further study aiming at potential clinical applicability.
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Giszter SF. Spinal primitives and intra-spinal micro-stimulation (ISMS) based prostheses: a neurobiological perspective on the "known unknowns" in ISMS and future prospects. Front Neurosci 2015; 9:72. [PMID: 25852454 PMCID: PMC4367173 DOI: 10.3389/fnins.2015.00072] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 02/18/2014] [Indexed: 11/13/2022] Open
Abstract
The current literature on Intra-Spinal Micro-Stimulation (ISMS) for motor prostheses is reviewed in light of neurobiological data on spinal organization, and a neurobiological perspective on output motor modularity, ISMS maps, stimulation combination effects, and stability. By comparing published data in these areas, the review identifies several gaps in current knowledge that are crucial to the development of effective intraspinal neuroprostheses. Gaps can be categorized into a lack of systematic and reproducible details of: (a) Topography and threshold for ISMS across the segmental motor system, the topography of autonomic recruitment by ISMS, and the coupling relations between these two types of outputs in practice. (b) Compositional rules for ISMS motor responses tested across the full range of the target spinal topographies. (c) Rules for ISMS effects' dependence on spinal cord state and neural dynamics during naturally elicited or ISMS triggered behaviors. (d) Plasticity of the compositional rules for ISMS motor responses, and understanding plasticity of ISMS topography in different spinal cord lesion states, disease states, and following rehabilitation. All these knowledge gaps to a greater or lesser extent require novel electrode technology in order to allow high density chronic recording and stimulation. The current lack of this technology may explain why these prominent gaps in the ISMS literature currently exist. It is also argued that given the "known unknowns" in the current ISMS literature, it may be prudent to adopt and develop control schemes that can manage the current results with simple superposition and winner-take-all interactions, but can also incorporate the possible plastic and stochastic dynamic interactions that may emerge in fuller analyses over longer terms, and which have already been noted in some simpler model systems.
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Affiliation(s)
- Simon F Giszter
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, Drexel University Philadelphia, PA, USA ; School of Biomedical Engineering and Health Systems, Drexel University Philadelphia, PA, USA
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Rapid prototyping of multi-scale biomedical microdevices by combining additive manufacturing technologies. Biomed Microdevices 2015; 16:617-27. [PMID: 24781883 DOI: 10.1007/s10544-014-9864-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The possibility of designing and manufacturing biomedical microdevices with multiple length-scale geometries can help to promote special interactions both with their environment and with surrounding biological systems. These interactions aim to enhance biocompatibility and overall performance by using biomimetic approaches. In this paper, we present a design and manufacturing procedure for obtaining multi-scale biomedical microsystems based on the combination of two additive manufacturing processes: a conventional laser writer to manufacture the overall device structure, and a direct-laser writer based on two-photon polymerization to yield finer details. The process excels for its versatility, accuracy and manufacturing speed and allows for the manufacture of microsystems and implants with overall sizes up to several millimeters and with details down to sub-micrometric structures. As an application example we have focused on manufacturing a biomedical microsystem to analyze the impact of microtextured surfaces on cell motility. This process yielded a relevant increase in precision and manufacturing speed when compared with more conventional rapid prototyping procedures.
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Gunasekera B, Saxena T, Bellamkonda R, Karumbaiah L. Intracortical recording interfaces: current challenges to chronic recording function. ACS Chem Neurosci 2015; 6:68-83. [PMID: 25587704 DOI: 10.1021/cn5002864] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Brain Computer Interfaces (BCIs) offer significant hope to tetraplegic and paraplegic individuals. This technology relies on extracting and translating motor intent to facilitate control of a computer cursor or to enable fine control of an external assistive device such as a prosthetic limb. Intracortical recording interfaces (IRIs) are critical components of BCIs and consist of arrays of penetrating electrodes that are implanted into the motor cortex of the brain. These multielectrode arrays (MEAs) are responsible for recording and conducting neural signals from local ensembles of neurons in the motor cortex with the high speed and spatiotemporal resolution that is required for exercising control of external assistive prostheses. Recent design and technological innovations in the field have led to significant improvements in BCI function. However, long-term (chronic) BCI function is severely compromised by short-term (acute) IRI recording failure. In this review, we will discuss the design and function of current IRIs. We will also review a host of recent advances that contribute significantly to our overall understanding of the cellular and molecular events that lead to acute recording failure of these invasive implants. We will also present recent improvements to IRI design and provide insights into the futuristic design of more chronically functional IRIs.
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Affiliation(s)
- Bhagya Gunasekera
- Regenerative
Bioscience Center, ADS Complex, The University of Georgia, Athens, Georgia 30602-2771, United States
| | - Tarun Saxena
- Wallace
H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0535, United States
| | - Ravi Bellamkonda
- Wallace
H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0535, United States
| | - Lohitash Karumbaiah
- Regenerative
Bioscience Center, ADS Complex, The University of Georgia, Athens, Georgia 30602-2771, United States
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Reeder J, Kaltenbrunner M, Ware T, Arreaga-Salas D, Avendano-Bolivar A, Yokota T, Inoue Y, Sekino M, Voit W, Sekitani T, Someya T. Mechanically adaptive organic transistors for implantable electronics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2014; 26:4967-4973. [PMID: 24733490 DOI: 10.1002/adma.201400420] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Revised: 02/19/2014] [Indexed: 06/03/2023]
Abstract
A unique form of adaptive electronics is demonstrated, which change their mechanical properties from rigid and planar to soft and compliant, in order to enable soft and conformal wrapping around 3D objects, including biological tissue. These devices feature excellent mechanical robustness and maintain initial electrical properties even after changing shape and stiffness.
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Affiliation(s)
- Jonathan Reeder
- Electrical and Electronic Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan; Department of Materials Science and Engineering, The University of Texas at Dallas, 800 W. Campbell Rd., Richardson, Texas, 75080-3021, USA
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Carlborg CF, Vastesson A, Liu Y, van der Wijngaart W, Johansson M, Haraldsson T. Functional off-stoichiometry thiol-ene-epoxy thermosets featuring temporally controlled curing stages via an UV/UV dual cure process. ACTA ACUST UNITED AC 2014. [DOI: 10.1002/pola.27276] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Carl Fredrik Carlborg
- Department of Micro and Nanosystems; KTH Royal Institute of Technology; Osquldas v. 10 SE-100 44 Stockholm Sweden
| | - Alexander Vastesson
- Department of Micro and Nanosystems; KTH Royal Institute of Technology; Osquldas v. 10 SE-100 44 Stockholm Sweden
| | - Yitong Liu
- Department of Micro and Nanosystems; KTH Royal Institute of Technology; Osquldas v. 10 SE-100 44 Stockholm Sweden
| | - Wouter van der Wijngaart
- Department of Micro and Nanosystems; KTH Royal Institute of Technology; Osquldas v. 10 SE-100 44 Stockholm Sweden
| | - Mats Johansson
- Department of Fibre and Polymer Technology; KTH Royal Institute of Technology; Teknikringen 48 SE-100 44 Stockholm Sweden
| | - Tommy Haraldsson
- Department of Micro and Nanosystems; KTH Royal Institute of Technology; Osquldas v. 10 SE-100 44 Stockholm Sweden
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