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Publications (10 of 13) Show all publications
Enrico, A., Buchmann, S., De Ferrari, F., Lin, Y., Wang, Y., Yue, W., . . . Zeglio, E. (2024). Cleanroom‐Free Direct Laser Micropatterning of Polymers for Organic Electrochemical Transistors in Logic Circuits and Glucose Biosensors. Advanced Science
Open this publication in new window or tab >>Cleanroom‐Free Direct Laser Micropatterning of Polymers for Organic Electrochemical Transistors in Logic Circuits and Glucose Biosensors
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2024 (English)In: Advanced Science, E-ISSN 2198-3844Article in journal (Refereed) Published
Abstract [en]

Organic electrochemical transistors (OECTs) are promising devices for bioelectronics, such as biosensors. However, current cleanroom-based microfabrication of OECTs hinders fast prototyping and widespread adoption of this technology for low-volume, low-cost applications. To address this limitation, a versatile and scalable approach for ultrafast laser microfabrication of OECTs is herein reported, where a femtosecond laser to pattern insulating polymers (such as parylene C or polyimide) is first used, exposing the underlying metal electrodes serving as transistor terminals (source, drain, or gate). After the first patterning step, conducting polymers, such as poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), or semiconducting polymers, are spin-coated on the device surface. Another femtosecond laser patterning step subsequently defines the active polymer area contributing to the OECT performance by disconnecting the channel and gate from the surrounding spin-coated film. The effective OECT width can be defined with high resolution (down to 2 µm) in less than a second of exposure. Micropatterning the OECT channel area significantly improved the transistor switching performance in the case of PEDOT:PSS-based transistors, speeding up the devices by two orders of magnitude. The utility of this OECT manufacturing approach is demonstrated by fabricating complementary logic (inverters) and glucose biosensors, thereby showing its potential to accelerate OECT research.

Place, publisher, year, edition, pages
Wiley, 2024
Keywords
conjugated polymer, direct writing, organic electrochemical transistor, poly(3, 4-ethylenedioxythiophene) polystyrene sulfonate, ultrashort pulsed lasers
National Category
Organic Chemistry Other Electrical Engineering, Electronic Engineering, Information Engineering Other Materials Engineering
Identifiers
urn:nbn:se:kth:diva-342521 (URN)10.1002/advs.202307042 (DOI)001142422700001 ()2-s2.0-85182492139 (Scopus ID)
Funder
Swedish Research Council, 2018‐03483Swedish Research Council, 2022‐04060Swedish Research Council, 2022‐02855Knut and Alice Wallenberg Foundation, 2015.0178Knut and Alice Wallenberg Foundation, 2020.0206Knut and Alice Wallenberg Foundation, 2021.0312Swedish Research Council, 2022-00374
Note

QC 20240123

Available from: 2024-01-23 Created: 2024-01-23 Last updated: 2024-02-06Bibliographically approved
Zeglio, E., Wang, Y., Jain, S., Lin, Y., Avila Ramirez, A. E., Feng, K., . . . Herland, A. (2024). Mixing Insulating Commodity Polymers with Semiconducting n‐type Polymers Enables High‐Performance Electrochemical Transistors. Advanced Materials, Article ID adma.202302624.
Open this publication in new window or tab >>Mixing Insulating Commodity Polymers with Semiconducting n‐type Polymers Enables High‐Performance Electrochemical Transistors
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2024 (English)In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, article id adma.202302624Article in journal (Refereed) Published
Abstract [en]

Diluting organic semiconductors with a host insulating polymer is used to increase the electronic mobility in organic electronic devices, such as thin film transistors, while considerably reducing material costs. In contrast to organic electronics, bioelectronic devices such as the organic electrochemical transistor (OECT) rely on both electronic and ionic mobility for efficient operation, making it challenging to integrate hydrophobic polymers as the predominant blend component. This work shows that diluting the n-type conjugated polymer p(N-T) with high molecular weight polystyrene (10 KDa) leads to OECTs with over three times better mobility-volumetric capacitance product (µC*) with respect to the pristine p(N-T) (from 4.3 to 13.4 F V−1 cm−1 s−1) while drastically decreasing the amount of conjugated polymer (six times less). This improvement in µC* is due to a dramatic increase in electronic mobility by two orders of magnitude, from 0.059 to 1.3 cm2 V−1 s−1 for p(N-T):Polystyrene 10 KDa 1:6. Moreover, devices made with this polymer blend show better stability, retaining 77% of the initial drain current after 60 minutes operation in contrast to 12% for pristine p(N-T). These results open a new generation of low-cost organic mixed ionic-electronic conductors where the bulk of the film is made by a commodity polymer.

Place, publisher, year, edition, pages
Wiley, 2024
National Category
Polymer Technologies Materials Engineering Nano Technology Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-345903 (URN)10.1002/adma.202302624 (DOI)2-s2.0-85187136336 (Scopus ID)
Funder
Knut and Alice Wallenberg Foundation, KAW2015.0178 2020.0206Knut and Alice Wallenberg Foundation, 2021.0312Swedish Research Council, 2018–03483Swedish Research Council, 2022‐04060Swedish Research Council, 2022‐02855Karolinska Institute, 1‐249/2019KTH Royal Institute of Technology, VF‐2019‐0110
Note

QC 20240429

Available from: 2024-04-25 Created: 2024-04-25 Last updated: 2024-04-29Bibliographically approved
Wang, Y., Zhu, G., Zeglio, E., Castillo, T. C., Haseena, S., Ravva, M. K., . . . Yue, W. (2023). n-Type Organic Electrochemical Transistors with High Transconductance and Stability. Chemistry of Materials, 35(2), 405-415
Open this publication in new window or tab >>n-Type Organic Electrochemical Transistors with High Transconductance and Stability
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2023 (English)In: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 35, no 2, p. 405-415Article in journal (Refereed) Published
Abstract [en]

An n-type conjugated polymer based on diazaisoindigo (AIID) and fluorinated thiophene units is introduced. Combining the strong electron-accepting properties of AIID with backbone fluorination produced gAIID-2FT, leading to organic electrochemical transistors (OECTs) with normalized values of 4.09 F cm-1 V-1 s-1 and a normalized transconductance (gm,norm) of 0.94 S cm-1. The resulting OECTs exhibit exceptional operational stability and long shelf-life in ambient conditions, preserving 100% of the original maximum drain current after over 3 h of continuous operation and 28 days of storage in the air. Our work highlights the advantages of integrating strong electron acceptors with donor fluorination to boost the performance and stability of n-type OECTs.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2023
National Category
Condensed Matter Physics Materials Chemistry
Identifiers
urn:nbn:se:kth:diva-335755 (URN)10.1021/acs.chemmater.2c02447 (DOI)000923050400001 ()2-s2.0-85146133468 (Scopus ID)
Note

QC 20230911

Available from: 2023-09-11 Created: 2023-09-11 Last updated: 2023-09-11Bibliographically approved
Buchmann, S., Enrico, A., Holzreuter, M. A., Reid, M. S., Zeglio, E., Niklaus, F., . . . Herland, A. (2023). Probabilistic cell seeding and non-autofluorescent 3D-printed structures as scalable approach for multi-level co-culture modeling. Materials Today Bio, 21, 100706-100706, Article ID 100706.
Open this publication in new window or tab >>Probabilistic cell seeding and non-autofluorescent 3D-printed structures as scalable approach for multi-level co-culture modeling
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2023 (English)In: Materials Today Bio, ISSN 2590-0064, Vol. 21, p. 100706-100706, article id 100706Article in journal (Refereed) Published
Abstract [en]

To model complex biological tissue in vitro, a specific layout for the position and numbers of each cell type isnecessary. Establishing such a layout requires manual cell placement in three dimensions (3D) with micrometricprecision, which is complicated and time-consuming. Moreover, 3D printed materials used in compartmentalizedmicrofluidic models are opaque or autofluorescent, hindering parallel optical readout and forcing serial charac-terization methods, such as patch-clamp probing. To address these limitations, we introduce a multi-level co-culture model realized using a parallel cell seeding strategy of human neurons and astrocytes on 3D structuresprinted with a commercially available non-autofluorescent resin at micrometer resolution. Using a two-stepstrategy based on probabilistic cell seeding, we demonstrate a human neuronal monoculture that forms net-works on the 3D printed structure and can establish cell-projection contacts with an astrocytic-neuronal co-cultureseeded on the glass substrate. The transparent and non-autofluorescent printed platform allows fluorescence-based immunocytochemistry and calcium imaging. This approach provides facile multi-level compartmentaliza-tion of different cell types and routes for pre-designed cell projection contacts, instrumental in studying complextissue, such as the human brain.

Place, publisher, year, edition, pages
Elsevier BV, 2023
Keywords
Two-photon polymerization Neurons Astrocytes Calcium imaging Co-culture models IP-Visio
National Category
Nano Technology Bio Materials Cell Biology
Identifiers
urn:nbn:se:kth:diva-331732 (URN)10.1016/j.mtbio.2023.100706 (DOI)001030630300001 ()37435551 (PubMedID)2-s2.0-85166735644 (Scopus ID)
Note

Correction in Materials Today Bio, vol. 23. DOI:10.1016/j.mtbio.2023.100892

QC 20231221

Available from: 2023-07-14 Created: 2023-07-14 Last updated: 2024-02-06Bibliographically approved
McCuskey, S. R., Chatsirisupachai, J., Zeglio, E., Parlak, O., Panoy, P., Herland, A., . . . Nguyen, T.-Q. (2022). Current Progress of Interfacing Organic Semiconducting Materials with Bacteria. Chemical Reviews, 122(4), 4791-4825
Open this publication in new window or tab >>Current Progress of Interfacing Organic Semiconducting Materials with Bacteria
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2022 (English)In: Chemical Reviews, ISSN 0009-2665, E-ISSN 1520-6890, Vol. 122, no 4, p. 4791-4825Article, review/survey (Refereed) Published
Abstract [en]

Microbial bioelectronics require interfacing microorganisms with electrodes. The resulting abiotic/biotic platforms provide the basis of a range of technologies, including energy conversion and diagnostic assays. Organic semiconductors (OSCs) provide a unique strategy to modulate the interfaces between microbial systems and external electrodes, thereby improving the performance of these incipient technologies. In this review, we explore recent progress in the field on how OSCs, and related materials capable of charge transport, are being used within the context of microbial systems, and more specifically bacteria. We begin by examining the electrochemical communication modes in bacteria and the biological basis for charge transport. Different types of synthetic organic materials that have been designed and synthesized for interfacing and interrogating bacteria are discussed next, followed by the most commonly used characterization techniques for evaluating transport in microbial, synthetic, and hybrid systems. A range of applications is subsequently examined, including biological sensors and energy conversion systems. The review concludes by summarizing what has been accomplished so far and suggests future design approaches for OSC bioelectronics materials and technologies that hybridize characteristic properties of microbial and OSC systems.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2022
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-311513 (URN)10.1021/acs.chemrev.1c00487 (DOI)000781182800011 ()34714064 (PubMedID)2-s2.0-85118780917 (Scopus ID)
Note

QC 20220503

Available from: 2022-05-03 Created: 2022-05-03 Last updated: 2022-06-25Bibliographically approved
Wang, Y., Zeglio, E., Wang, L., Cong, S., Zhu, G., Liao, H., . . . McCulloch, I. (2022). Green Synthesis of Lactone-Based Conjugated Polymers for n-Type Organic Electrochemical Transistors. Advanced Functional Materials, 32(16), Article ID 2111439.
Open this publication in new window or tab >>Green Synthesis of Lactone-Based Conjugated Polymers for n-Type Organic Electrochemical Transistors
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2022 (English)In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 32, no 16, article id 2111439Article in journal (Refereed) Published
Abstract [en]

As new and better materials are implemented for organic electrochemical transistors (OECTs), it becomes increasingly important to adopt more economic and environmentally friendly synthesis pathways with respect to conventional transition-metal-catalyzed polymerizations. Herein, a series of novel n-type donor–acceptor-conjugated polymers based on glycolated lactone and bis-isatin units are reported. All the polymers are synthesized via green and metal-free aldol polymerization. The strong electron-deficient lactone-building blocks provide low-lying lowest unoccupied molecular orbital (LUMO) and the rigid backbone needed for efficient electron mobility up to 0.07 cm2 V−1 s−1. Instead, polar atoms in the backbone and ethylene glycol side chains contribute to the ionic conductivity. The resulting OECTs exhibit a normalized maximum transconductance gm,norm of 0.8 S cm−1 and a μC* of 6.7 F cm−1 V−1 s−1. Data on the microstructure show that such device performance originates from a unique porous morphology together with a highly disordered amorphous microstructure, leading to efficient ion-to-electron coupling. Overall, the design strategy provides an inexpensive and metal-free polymerization route for high-performing n-type OECTs. 

Place, publisher, year, edition, pages
Wiley, 2022
Keywords
conjugated polymer, green chemistry, n-type organic semiconductor, organic electrochemical transistor, sustainable design, Conjugated polymers, Ethylene, Ethylene glycol, Functional materials, Ketones, Microstructure, Molecular orbitals, Morphology, Polymerization, Transition metals, Based conjugated polymers, Catalyzed polymerization, Conventional transitions, Donor-acceptor conjugated polymers, Environmentally friendly synthesis, Green synthesis, Metal free, Metal-catalyzed, Organic electrochemical transistors, Synthesis pathways, Esters
National Category
Other Physics Topics Energy Engineering Energy Systems
Identifiers
urn:nbn:se:kth:diva-317506 (URN)10.1002/adfm.202111439 (DOI)000737074000001 ()2-s2.0-85122159843 (Scopus ID)
Note

QC 20220919

Available from: 2022-09-19 Created: 2022-09-19 Last updated: 2022-09-19Bibliographically approved
Gu, M., Travaglini, L., Hopkins, J., Ta, D., Lauto, A., Wagner, P., . . . Mawad, D. (2022). Molecular design of an electropolymerized copolymer with carboxylic and sulfonic acid functionalities. Synthetic metals, 285, 117029, Article ID 117029.
Open this publication in new window or tab >>Molecular design of an electropolymerized copolymer with carboxylic and sulfonic acid functionalities
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2022 (English)In: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 285, p. 117029-, article id 117029Article in journal (Refereed) Published
Abstract [en]

Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is the most researched conjugated polymer in the field of organic bioelectronics. The conjugated PEDOT backbone features good redox stability in aqueous electrolyte, and low oxidation potential. However, PEDOT:PSS has two major drawbacks. The PEDOT backbone lacks biofunctionality, limiting the fine tuning of its interface with the biological environment. The dopant PSS is insulating, resulting in a decrease in the capacitance of the polymer. Here, we describe the design of a random copolymer, P(EDOTCOOH-co-EDOTS), based on EDOT monomers functionalized with sulfonic and carboxylic acid groups. The copolymer was successfully synthesized by electropolymerization as confirmed by X-ray photoelectron spectroscopy. Contact angle measurements illustrated the high hydrophilicity of the P (EDOTCOOH-co-EDOTS) (28 & PLUSMN; 6 & nbsp;), attributed to the sulfonate group in the side chains. This in turn led to a higher water penetration into the copolymer film, enhancing significantly its volumetric capacitance (69 & PLUSMN; 4 F cm(-3)), and thereby, its performance when used as an active channel in an organic electrochemical transistor. Of note, we incorporated the sulfonate group in its sodium salt form retaining its highly ionized properties. This is the first instance of utilizing an uncapped, ionized sulfonate group covalently bound to the backbone of a polymer, where the resultant polymer is oxidized at very low potentials, as well as stable and electroactive in aqueous electrolytes. Furthermore, our molecular design to incorporate carboxylic acid groups paves the way for the development of conjugated polymers that can be tailored for bioelectronic applications.

Place, publisher, year, edition, pages
Elsevier BV, 2022
Keywords
PEDOT, Ionized, Conjugated copolymer, Self-doped, Sulfonate
National Category
Analytical Chemistry
Identifiers
urn:nbn:se:kth:diva-312807 (URN)10.1016/j.synthmet.2022.117029 (DOI)000791690500002 ()2-s2.0-85124508018 (Scopus ID)
Note

QC 20220525

Available from: 2022-05-25 Created: 2022-05-25 Last updated: 2022-06-25Bibliographically approved
Eslami, M., Zeglio, E., Alosaimi, G., Yan, Y., Ruprai, H., Macmillan, A., . . . Mawad, D. (2020). A One Step Procedure toward Conductive Suspensions of Liposome-Polyaniline Complexes. Macromolecular Bioscience, 20(11), Article ID 2000103.
Open this publication in new window or tab >>A One Step Procedure toward Conductive Suspensions of Liposome-Polyaniline Complexes
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2020 (English)In: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, Vol. 20, no 11, article id 2000103Article in journal (Refereed) Published
Abstract [en]

Interaction of conjugated polymers with liposomes is an attractive approach that benefits from both systems’ characteristics such as electroactivity and enhanced interaction with cells. Conjugated polymer-liposome complexes have been investigated for bioimaging, drug delivery, and photothermal therapy. Their fabrication has largely been achieved by multistep procedures that require first the synthesis and processing of the conjugated polymer. Here, a new one step fabrication approach is reported based on in situ polymerization of a conjugated monomer precursor around liposomes. Polyaniline (PANI) doped with phytic acid is synthesized via oxidative polymerization in the presence of 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC) vesicles to produce a conductive aqueous suspension of Liposome-PANI complexes. PANI interacts with liposomes without disrupting the bilayer as shown using differential scanning calorimetry and fluorescence quenching studies of the hydrophobic Nile red probe. The electronic conductivity of the Liposome-PANI complexes, which stems from the doped PANI accessible on the liposome surface, is confirmed using conductive atomic force microscopy and electrochemical impedance spectroscopy. Further, short-term in vitro cell studies show that the complexes colocalize with the cell membrane without reducing cell proliferation. This study presents a novel fabrication route to conductive suspensions of conjugated polymer-liposome complexes suitable for potential applications at the biointerface.

Place, publisher, year, edition, pages
Wiley, 2020
Keywords
complex, conductive suspensions, conjugated polymers, liposomes, Cell proliferation, Cells, Cytology, Differential scanning calorimetry, Electrochemical impedance spectroscopy, Polymerization, Quenching, Suspensions (fluids), Synthesis (chemical), Conductive atomic force microscopy, Electronic conductivity, In-situ polymerization, Multi-step procedures, Oxidative polymerization, Photothermal therapy, Polyaniline complexes, Synthesis and processing, Drug delivery
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-287138 (URN)10.1002/mabi.202000103 (DOI)000594835300005 ()32537900 (PubMedID)2-s2.0-85086400600 (Scopus ID)
Note

QC 20201203

Available from: 2020-12-03 Created: 2020-12-03 Last updated: 2022-06-25Bibliographically approved
Travaglini, L., Micolich, A. P., Cazorla, C., Zeglio, E., Lauto, A. & Mawad, D. (2020). Single-Material OECT-Based Flexible Complementary Circuits Featuring Polyaniline in Both Conducting Channels. Advanced Functional Materials
Open this publication in new window or tab >>Single-Material OECT-Based Flexible Complementary Circuits Featuring Polyaniline in Both Conducting Channels
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2020 (English)In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028Article in journal (Refereed) Published
Abstract [en]

The organic electrochemical transistor (OECT) with a conjugated polymer as the active material is the elementary unit of organic bioelectronic devices. Improved functionalities, such as low power consumption, can be achieved by building complementary circuits featuring two or more OECTs. Complementary circuits commonly combine both p- and n-type transistors to reduce power draw. While p-type OECTs are readily available, n-type OECTs are less common mainly due to poor stability of the n-type active channel material in aqueous electrolyte. Here, a complementary circuit is made using a pair of OECTs having polyaniline (PANI) as the channel material in both transistors. PANI, with a finite electrochemical window accessible at voltages lower than 1 V, exhibits a peak in current versus gate voltage when used as an active channel in an OECT. The current peak has two slopes, one n-like and one p-like, which correspond to different electrochemical regimes of the same underlying conjugated polymer. The electrochemistry enables the design of a complementary circuit using only PANI as the channel material. The PANI-based circuit is shown to have excellent performance with gain of ≈7 and is transferred on a flexible biocompatible chitosan substrate with demonstrated operation in aqueous electrolyte.

Place, publisher, year, edition, pages
Wiley-VCH Verlagsgesellschaft, 2020
Keywords
bioelectronic devices, complementary circuits, organic electrochemical transistors, polyaniline, Biocompatibility, Conjugated polymers, Electrochemistry, Electrolytes, Low power electronics, Timing circuits, Aqueous electrolyte, Bioelectronic device, Conducting channels, Electrochemical window, Low-power consumption, Polyanilines (PAni), Flexible electronics
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-287113 (URN)10.1002/adfm.202007205 (DOI)000577742500001 ()2-s2.0-85092551831 (Scopus ID)
Note

QCR 20201203

AIP

Available from: 2020-12-03 Created: 2020-12-03 Last updated: 2022-06-25Bibliographically approved
Zeglio, E., Rutz, A. L., Winkler, T., Malliaras, G. G. & Herland, A. (2019). Conjugated Polymers for Assessing and Controlling Biological Functions. Advanced Materials, 31(22), Article ID 1806712.
Open this publication in new window or tab >>Conjugated Polymers for Assessing and Controlling Biological Functions
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2019 (English)In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 31, no 22, article id 1806712Article in journal (Refereed) Published
Abstract [en]

The field of organic bioelectronics is advancing rapidly in the development of materials and devices to precisely monitor and control biological signals. Electronics and biology can interact on multiple levels: organs, complex tissues, cells, cell membranes, proteins, and even small molecules. Compared to traditional electronic materials such as metals and inorganic semiconductors, conjugated polymers (CPs) have several key advantages for biological interactions: tunable physiochemical properties, adjustable form factors, and mixed conductivity (ionic and electronic). Herein, the use of CPs in five biologically oriented research topics, electrophysiology, tissue engineering, drug release, biosensing, and molecular bioelectronics, is discussed. In electrophysiology, implantable devices with CP coating or CP-only electrodes are showing improvements in signal performance and tissue interfaces. CP-based scaffolds supply highly favorable static or even dynamic interfaces for tissue engineering. CPs also enable delivery of drugs through a variety of mechanisms and form factors. For biosensing, CPs offer new possibilities to incorporate biological sensing elements in a conducting matrix. Molecular bioelectronics is today used to incorporate (opto)electronic functions in living tissue. Under each topic, the limits of the utility of CPs are discussed and, overall, the major challenges toward implementation of CPs and their devices to real-world applications are highlighted.

Keywords
biosensors, conjugated polymers, electrophysiology, organic bioelectronics, tissue engineering
National Category
Textile, Rubber and Polymeric Materials
Research subject
Technology and Health
Identifiers
urn:nbn:se:kth:diva-250560 (URN)10.1002/adma.201806712 (DOI)000475696300006 ()30861237 (PubMedID)2-s2.0-85062980044 (Scopus ID)
Funder
EU, Horizon 2020, 797506EU, Horizon 2020, 797777Knut and Alice Wallenberg FoundationThe Royal Swedish Academy of SciencesGöran Gustafsson Foundation for Research in Natural Sciences and Medicine
Note

QC 20190521

Available from: 2019-04-30 Created: 2019-04-30 Last updated: 2024-03-15Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-6428-0633

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