Integration of hydrogels in microfabrication processes for bioelectronic medicine: Progress and outlook

Recent research aiming at the development of electroceuticals for the treatment of medical conditions such as degenerative diseases, cardiac arrhythmia and chronic pain, has given rise to microfabricated implanted bioelectronic devices capable of interacting with host biological tissues in synergistic modalities. Owing to their multimodal affinity to biological tissues, hydrogels have emerged as promising interface materials for bioelectronic devices. Here, we review the state-of-the-art and forefront in the techniques used by research groups for the integration of hydrogels into the microfabrication processes of bioelectronic devices, and present the manufacturability challenges to unlock their further clinical deployment.

[1]  Hengjia Zhu,et al.  Multifunctional tendon-mimetic hydrogels , 2023, Science advances.

[2]  Mahima Bansal,et al.  Electrically Responsive Release of Proteins from Conducting Polymer Hydrogels. , 2023, Acta biomaterialia.

[3]  P. Le,et al.  Synthesis, properties, and applications of chitosan hydrogels as anti-inflammatory drug delivery system , 2022, Journal of Porous Materials.

[4]  Xuanhe Zhao,et al.  Hydrogel interfaces for merging humans and machines , 2022, Nature Reviews Materials.

[5]  Yang Cong,et al.  Hydrogel-Tissue Interface Interactions for Implantable Flexible Bioelectronics. , 2022, Langmuir : the ACS journal of surfaces and colloids.

[6]  Hongzhuo Liu,et al.  Basic principles in functional hydrogels towards biotherapeutics , 2022, Materials & Design.

[7]  Evon S. Ereifej,et al.  Neuroinflammatory Gene Expression Analysis Reveals Pathways of Interest as Potential Targets to Improve the Recording Performance of Intracortical Microelectrodes , 2022, Cells.

[8]  A. Poater,et al.  pH-Responsive Gelation in Metallo-Supramolecular Polymers Based on the Protic Pyridinedicarboxamide Ligand , 2022, Chemistry of Materials.

[9]  S. Ko,et al.  Digital selective transformation and patterning of highly conductive hydrogel bioelectronics by laser-induced phase separation , 2022, Science advances.

[10]  J. Cleland,et al.  Synchronized diaphragmatic stimulation for heart failure using the VisONE system: a first‐in‐patient study , 2022, ESC heart failure.

[11]  L. Zollo,et al.  A Soft Zwitterionic Hydrogel as Potential Coating on a Polyimide Surface to Reduce Foreign Body Reaction to Intraneural Electrodes , 2022, Molecules.

[12]  Jie Huang,et al.  Recent Development of Conductive Hydrogels for Tissue Engineering: Review and Perspective. , 2022, Macromolecular bioscience.

[13]  V. Nissapatorn,et al.  Drug Delivery Strategies and Biomedical Significance of Hydrogels: Translational Considerations , 2022, Pharmaceutics.

[14]  Gregory L Brown,et al.  Transcranial electrical stimulation in neurological disease , 2022, Neural regeneration research.

[15]  L. Fadiga,et al.  On the longevity of flexible neural interfaces: Establishing biostability of polyimide-based intracortical implants. , 2022, Biomaterials.

[16]  G. Fridman,et al.  A Hydrogel-Based Microfluidic Nerve Cuff for Neuromodulation of Peripheral Nerves , 2021, Micromachines.

[17]  Y. Lai,et al.  Self-assembled nanocomposite hydrogels enhanced by nanoparticles phosphonate-magnesium coordination for bone regeneration , 2021, Applied Materials Today.

[18]  Maria Vomero,et al.  Biomedical Microtechnologies Beyond Scholarly Impact , 2021, Micromachines.

[19]  T. Oh,et al.  Self-Healing Hydrogels: Preparation, Mechanism and Advancement in Biomedical Applications , 2021, Polymers.

[20]  L. Korley,et al.  Screen Printing Tissue Models Using Chemically Cross-Linked Hydrogel Systems: A Simple Approach To Efficiently Make Highly Tunable Matrices. , 2021, ACS biomaterials science & engineering.

[21]  Mahima Bansal,et al.  An interpenetrating and patternable conducting polymer hydrogel for electrically stimulated release of glutamate. , 2021, Acta biomaterialia.

[22]  J. Gong,et al.  Bioinspired Underwater Adhesives , 2021, Advanced materials.

[23]  Wei‐Chen Huang,et al.  Fabrication of Soft Tissue Scaffold-Mimicked Microelectrode Arrays Using Enzyme-Mediated Transfer Printing , 2021, Micromachines.

[24]  Ji Liu,et al.  Trigger‐Detachable Hydrogel Adhesives for Bioelectronic Interfaces , 2021, Advanced Functional Materials.

[25]  Wei Liu,et al.  Thermo-sensitive electroactive hydrogel combined with electrical stimulation for repair of spinal cord injury , 2021, Journal of Nanobiotechnology.

[26]  Xiaodong Chen,et al.  A Stretchable and Transparent Electrode Based on PEGylated Silk Fibroin for In Vivo Dual‐Modal Neural‐Vascular Activity Probing , 2021, Advanced materials.

[27]  Kejia Zhu,et al.  Copolymer hydrogel as self-standing electrode for high performance all-hydrogel-state supercapacitor , 2021, Journal of Materials Science.

[28]  S. M. Sapuan,et al.  Effect of glycerol plasticizer loading on the physical, mechanical, thermal, and barrier properties of arrowroot (Maranta arundinacea) starch biopolymers , 2021, Scientific Reports.

[29]  I. Plazl,et al.  Development of an electrically responsive hydrogel for programmable in situ immobilization within a microfluidic device. , 2021, Soft matter.

[30]  Christina M. Tringides,et al.  Viscoelastic surface electrode arrays to interface with viscoelastic tissues , 2021, Nature Nanotechnology.

[31]  Fanfan Fu,et al.  Interpenetrating PAA-PEDOT conductive hydrogels for flexible skin sensors , 2021, Journal of Materials Chemistry C.

[32]  Eric A. Appel,et al.  Translational Applications of Hydrogels , 2021, Chemical reviews.

[33]  S. Lacour,et al.  Dimensional scaling of thin-film stimulation electrode systems in translational research , 2021, Journal of neural engineering.

[34]  Guihua Yu,et al.  Balancing the mechanical, electronic, and self-healing properties in conductive self-healing hydrogel for wearable sensor applications. , 2021, Materials horizons.

[35]  Fabien B. Wagner,et al.  MRI‐Compatible and Conformal Electrocorticography Grids for Translational Research , 2021, Advanced science.

[36]  C. Majidi,et al.  An electrically conductive silver–polyacrylamide–alginate hydrogel composite for soft electronics , 2021, Nature Electronics.

[37]  C. Majidi,et al.  Publisher Correction: An electrically conductive silver–polyacrylamide–alginate hydrogel composite for soft electronics , 2021, Nature Electronics.

[38]  Shaoyi Jiang,et al.  High-strength and fibrous capsule–resistant zwitterionic elastomers , 2021, Science Advances.

[39]  H. Ouyang,et al.  Advanced hydrogels for the repair of cartilage defects and regeneration , 2020, Bioactive materials.

[40]  M. Tenje,et al.  A practical guide to microfabrication and patterning of hydrogels for biomimetic cell culture scaffolds , 2020, Organs-on-a-Chip.

[41]  W. Tremel,et al.  Poly(methyl ethylene phosphate) hydrogels: Degradable and cell-repellent alternatives to PEG-hydrogels , 2020, European Polymer Journal.

[42]  S. Takeuchi,et al.  Long‐Term Continuous Glucose Monitoring Using a Fluorescence‐Based Biocompatible Hydrogel Glucose Sensor , 2020, Advanced healthcare materials.

[43]  Sohee Kim,et al.  Development of a Polydimethylsiloxane‐Based Electrode Array for Electrocorticography , 2020, Advanced Materials Interfaces.

[44]  Narendra Pandala,et al.  Screen Printing to Create 3D Tissue Models. , 2020, ACS applied bio materials.

[45]  S. Ramesh,et al.  Fundamental Concepts of Hydrogels: Synthesis, Properties, and Their Applications , 2020, Polymers.

[46]  Giuseppe Schiavone,et al.  Guidelines to Study and Develop Soft Electrode Systems for Neural Stimulation , 2020, Neuron.

[47]  R. Pei,et al.  Recent progress of highly adhesive hydrogels as wound dressings. , 2020, Biomacromolecules.

[48]  Jiabing Fan,et al.  Inspired by Nature: Facile Design of Nanoclay–Organic Hydrogel Bone Sealant with Multifunctional Properties for Robust Bone Regeneration , 2020, Advanced functional materials.

[49]  Hongbo Zeng,et al.  Recent advances in designing conductive hydrogels for flexible electronics , 2020 .

[50]  M. Yamada,et al.  Sacrificial Alginate-Assisted Microfluidic Engineering of Cell-Supportive Protein Microfibers for Hydrogel-Based Cell Encapsulation , 2020, ACS omega.

[51]  Fritjof Helmchen,et al.  Opto‐E‐Dura: A Soft, Stretchable ECoG Array for Multimodal, Multiscale Neuroscience , 2020, Advanced healthcare materials.

[52]  Q. Barraud,et al.  Soft Printable Electrode Coating for Neural Interfaces. , 2020, ACS applied bio materials.

[53]  L. Fadiga,et al.  Conformable polyimide-based μECoGs: Bringing the electrodes closer to the signal source. , 2020, Biomaterials.

[54]  Patrick D. Loftus,et al.  Intrinsically stretchable electrode array enabled in vivo electrophysiological mapping of atrial fibrillation at cellular resolution , 2020, Proceedings of the National Academy of Sciences.

[55]  Hyunhyub Ko,et al.  Soft and ion-conducting hydrogel artificial tongue for astringency perception , 2020, Science Advances.

[56]  Cary A. Kuliasha,et al.  Integration of flexible polyimide arrays into soft extracellular matrix-based hydrogel materials for a tissue-engineered electronic nerve interface (TEENI) , 2020, Journal of Neuroscience Methods.

[57]  M. Ng,et al.  Insight into delivery of dermal fibroblast by non-biodegradable bacterial nanocellulose composite hydrogel on wound healing. , 2020, International journal of biological macromolecules.

[58]  A. Ahluwalia,et al.  Functionalized Enzyme-Responsive Biomaterials to Model Tissue Stiffening in vitro , 2020, Frontiers in Bioengineering and Biotechnology.

[59]  John R. Clegg,et al.  Hydrogels in the clinic , 2020, Bioengineering & translational medicine.

[60]  J. Weiland,et al.  Shape Morphable Hydrogel/Elastomer Bilayer for Implanted Retinal Electronics , 2020, Micromachines.

[61]  M. Gelinsky,et al.  3D printing of hydrogels: Rational design strategies and emerging biomedical applications , 2020 .

[62]  Xuanhe Zhao,et al.  3D printing of conducting polymers , 2020, Nature Communications.

[63]  Marco Capogrosso,et al.  Soft, Implantable Bioelectronic Interfaces for Translational Research , 2020, Advanced materials.

[64]  Hui Zhang,et al.  A low-cost, robust pressure-responsive smart window with dynamic switchable transmittance. , 2020, ACS applied materials & interfaces.

[65]  C. Ooi,et al.  Synthesis of poly(acrylamide)-based hydrogel for bio-sensing of hepatitis B core antigen , 2020 .

[66]  Kan Wang,et al.  Rapid Fabrication of Ready-to-Use Gelatin Scaffolds with Prevascular Networks Using Alginate Hollow Fibers as Sacrificial Templates. , 2020, ACS biomaterials science & engineering.

[67]  O. Nur,et al.  Conventional nanofabrication methods , 2020 .

[68]  B. Kaczmarek,et al.  The physical and chemical properties of hydrogels based on natural polymers , 2020 .

[69]  3D and 4D Printing of Polymer Nanocomposite Materials , 2020 .

[70]  Yilei Zhang,et al.  Hydrogels and hydrogel composites for 3D and 4D printing applications , 2020 .

[71]  Haeshin Lee,et al.  Increasing the Conductivity and Adhesion of Polypyrrole Hydrogels with Electropolymerized Polydopamine , 2019, Chemistry of Materials.

[72]  Wei Huang,et al.  Muscle-Inspired Self-Healing Hydrogels for Strain and Temperature Sensor. , 2019, ACS nano.

[73]  Azmi Khan,et al.  Interpenetrating polymer network as a pioneer drug delivery system: a review , 2019, Polymer Bulletin.

[74]  S. Matsuda,et al.  Clinical application of injectable growth factor for bone regeneration: a systematic review , 2019, Inflammation and regeneration.

[75]  Gibaek Lee,et al.  NIR-induced pH-reversible self-healing monitoring with smartphone by wireless hydrogel sensor , 2019, Sensors and Actuators B: Chemical.

[76]  Jae Young Lee,et al.  Micropatterned conductive hydrogels as multifunctional muscle-mimicking biomaterials: Graphene-incorporated hydrogels directly patterned with femtosecond laser ablation. , 2019, Acta biomaterialia.

[77]  I. Berindan‐Neagoe,et al.  Hydrogels Based Drug Delivery Synthesis, Characterization and Administration , 2019, Pharmaceutics.

[78]  B. Derby,et al.  Screen Printing of a Highly Conductive Graphene Ink for Flexible Printed Electronics. , 2019, ACS applied materials & interfaces.

[79]  Lilith M Caballero Aguilar,et al.  Growth factor delivery: Defining the next generation platforms for tissue engineering. , 2019, Journal of controlled release : official journal of the Controlled Release Society.

[80]  J. Michálek,et al.  Biomimetic modification of dual porosity poly(2-hydroxyethyl methacrylate) hydrogel scaffolds—porosity and stem cell growth evaluation , 2019, Biomedical materials.

[81]  T. Sun,et al.  Tough Triblock Copolymer Hydrogels with Different Micromorphologies for Medical and Sensory Materials , 2019, ACS Applied Polymer Materials.

[82]  K. Rebrin,et al.  Continuous monitoring of interstitial tissue oxygen using subcutaneous oxygen microsensors: In vivo characterization in healthy volunteers. , 2019, Microvascular research.

[83]  Mehdi Nikkhah,et al.  Self‐Healing Hydrogels: The Next Paradigm Shift in Tissue Engineering? , 2019, Advanced science.

[84]  S. Lacour,et al.  Thin Hydrogel–Elastomer Multilayer Encapsulation for Soft Electronics , 2019, Advanced Materials Technologies.

[85]  Sytze J Buwalda,et al.  Ultrafast in situ forming poly(ethylene glycol)‐poly(amido amine) hydrogels with tunable drug release properties via controllable degradation rates , 2019, European journal of pharmaceutics and biopharmaceutics : official journal of Arbeitsgemeinschaft fur Pharmazeutische Verfahrenstechnik e.V.

[86]  E. Khedr,et al.  Therapeutic Role of Transcranial Direct Current Stimulation in Alzheimer Disease Patients: Double-Blind, Placebo-Controlled Clinical Trial , 2019, Neurorehabilitation and neural repair.

[87]  O. Lieleg,et al.  Immune-informed mucin hydrogels evade fibrotic foreign body response in vivo , 2019, bioRxiv.

[88]  Rui L Reis,et al.  Injectable and Magnetic Responsive Hydrogels with Bioinspired Ordered Structures. , 2019, ACS biomaterials science & engineering.

[89]  Huanyu Cheng,et al.  Transfer Printing and its Applications in Flexible Electronic Devices , 2019, Nanomaterials.

[90]  Vladimir P. Torchilin,et al.  Hydrogels and Their Applications in Targeted Drug Delivery , 2019, Molecules.

[91]  Gina Lisignoli,et al.  Biomaterials: Foreign Bodies or Tuners for the Immune Response? , 2019, International journal of molecular sciences.

[92]  Zhenan Bao,et al.  Soft and elastic hydrogel-based microelectronics for localized low-voltage neuromodulation , 2019, Nature Biomedical Engineering.

[93]  Zhenan Bao,et al.  Soft and elastic hydrogel-based microelectronics for localized low-voltage neuromodulation , 2019, Nature Biomedical Engineering.

[94]  Mengmeng Kang,et al.  Self-recoverable and mechanical-reinforced hydrogel based on hydrophobic interaction with self-healable and conductive properties , 2018, Chemical Engineering Journal.

[95]  Lijuan Wang,et al.  Rheological behaviors and physical properties of plasticized hydrogel films developed from κ-carrageenan incorporating hydroxypropyl methylcellulose , 2018, Food Hydrocolloids.

[96]  P. Drummond,et al.  High‐Frequency (10 kHz) Electrical Stimulation of Peripheral Nerves for Treating Chronic Pain: A Double‐Blind Trial of Presence vs Absence of Stimulation , 2018, Neuromodulation : journal of the International Neuromodulation Society.

[97]  Matthias P Lutolf,et al.  3D Inkjet Printing of Complex, Cell-Laden Hydrogel Structures , 2018, Scientific Reports.

[98]  Jianzhong Fu,et al.  Interpenetrating polymer network hydrogels composed of chitosan and photocrosslinkable gelatin with enhanced mechanical properties for tissue engineering. , 2018, Materials science & engineering. C, Materials for biological applications.

[99]  Fabien B. Wagner,et al.  Targeted neurotechnology restores walking in humans with spinal cord injury , 2018, Nature.

[100]  Guoping Chen,et al.  Functional Hydrogels With Tunable Structures and Properties for Tissue Engineering Applications , 2018, Front. Chem..

[101]  Jong Seong Roh,et al.  Damage-Associated Molecular Patterns in Inflammatory Diseases , 2018, Immune network.

[102]  D. Poulikakos,et al.  On‐Demand Laser Printing of Picoliter‐Sized, Highly Viscous, Adhesive Fluids: Beyond Inkjet Limitations , 2018, Advanced Materials Interfaces.

[103]  Alexander M Seifalian,et al.  Conductive Polymers: Opportunities and Challenges in Biomedical Applications. , 2018, Chemical reviews.

[104]  Xiao Chuan Ong,et al.  Ultracompliant Hydrogel‐Based Neural Interfaces Fabricated by Aqueous‐Phase Microtransfer Printing , 2018 .

[105]  Ingelin Clausen,et al.  Measurement of Urinary Bladder Pressure: A Comparison of Methods , 2018, Sensors.

[106]  Jian Ping Gong,et al.  Tough Hydrogels with Fast, Strong, and Reversible Underwater Adhesion Based on a Multiscale Design , 2018, Advanced materials.

[107]  Z. Yin,et al.  Micropatterned Elastic Gold‐Nanowire/Polyacrylamide Composite Hydrogels for Wearable Pressure Sensors , 2018, Advanced Materials Technologies.

[108]  Qinghua Wu,et al.  Processing and Properties of Chitosan Inks for 3D Printing of Hydrogel Microstructures. , 2018, ACS biomaterials science & engineering.

[109]  A. Mikos,et al.  Injectable OPF/graphene oxide hydrogels provide mechanical support and enhance cell electrical signaling after implantation into myocardial infarct , 2018, Theranostics.

[110]  Chih-Hwa Chen,et al.  Hydrogels for the Application of Articular Cartilage Tissue Engineering: A Review of Hydrogels , 2018 .

[111]  Haeshin Lee,et al.  Polydopamine Surface Chemistry: A Decade of Discovery. , 2018, ACS applied materials & interfaces.

[112]  Jing Liu,et al.  Enhanced mechanical properties and gelling ability of gelatin hydrogels reinforced with chitin whiskers , 2018 .

[113]  Z. Suo,et al.  Hydrogel ionotronics , 2018, Nature Reviews Materials.

[114]  Seung Yun Nam,et al.  ECM Based Bioink for Tissue Mimetic 3D Bioprinting. , 2018, Advances in experimental medicine and biology.

[115]  X. Sui,et al.  Facile fabrication of redox/pH dual stimuli responsive cellulose hydrogel. , 2017, Carbohydrate polymers.

[116]  Takashi D Y Kozai,et al.  Understanding the Inflammatory Tissue Reaction to Brain Implants To Improve Neurochemical Sensing Performance. , 2017, ACS chemical neuroscience.

[117]  Yu Zhou,et al.  Visual in vivo degradation of injectable hydrogel by real-time and non-invasive tracking using carbon nanodots as fluorescent indicator. , 2017, Biomaterials.

[118]  Michael Bruns,et al.  An interpenetrating, microstructurable and covalently attached conducting polymer hydrogel for neural interfaces. , 2017, Acta biomaterialia.

[119]  F. Du,et al.  Supersensitive Oxidation-Responsive Biodegradable PEG Hydrogels for Glucose-Triggered Insulin Delivery. , 2017, ACS applied materials & interfaces.

[120]  K. Leong,et al.  3D Bioprinting of Highly Thixotropic Alginate/Methylcellulose Hydrogel with Strong Interface Bonding. , 2017, ACS applied materials & interfaces.

[121]  Quankang Wang,et al.  A Bioinspired Mineral Hydrogel as a Self‐Healable, Mechanically Adaptable Ionic Skin for Highly Sensitive Pressure Sensing , 2017, Advanced materials.

[122]  Pengchen Zhu,et al.  Effects of electrochemical reaction and surface morphology on electroactive surface area of porous copper manufactured by Lost Carbonate Sintering , 2017 .

[123]  Quanli Li,et al.  In vivo remineralization of dentin using an agarose hydrogel biomimetic mineralization system , 2017, Scientific Reports.

[124]  M. Grinstaff,et al.  On-Demand Dissolution of Chemically Cross-Linked Hydrogels. , 2017, Accounts of chemical research.

[125]  J. J. Siegel,et al.  Ultraflexible nanoelectronic probes form reliable, glial scar–free neural integration , 2017, Science Advances.

[126]  C. Siedlecki,et al.  4.18 Surface Texturing and Control of Bacterial Adhesion , 2017 .

[127]  Hyeongjin Lee,et al.  Strategy to Achieve Highly Porous/Biocompatible Macroscale Cell Blocks, Using a Collagen/Genipin-bioink and an Optimal 3D Printing Process. , 2016, ACS applied materials & interfaces.

[128]  M. in het Panhuis,et al.  Self‐Healing Hydrogels , 2016, Advanced materials.

[129]  Jochen Guck,et al.  Materials and technologies for soft implantable neuroprostheses , 2016, Nature Reviews Materials.

[130]  Hyunhyub Ko,et al.  Octopus‐Inspired Smart Adhesive Pads for Transfer Printing of Semiconducting Nanomembranes , 2016, Advanced materials.

[131]  Donghyun Lee,et al.  Multifunctional hydrogel coatings on the surface of neural cuff electrode for improving electrode-nerve tissue interfaces. , 2016, Acta biomaterialia.

[132]  Lars Hoff,et al.  Improved design of an implantable heart monitoring device , 2016, 2016 Symposium on Design, Test, Integration and Packaging of MEMS/MOEMS (DTIP).

[133]  Shinji Sugiura,et al.  Hydrogel microfabrication technology toward three dimensional tissue engineering , 2016, Regenerative therapy.

[134]  Dimiter Prodanov,et al.  Mechanical and Biological Interactions of Implants with the Brain and Their Impact on Implant Design , 2016, Front. Neurosci..

[135]  Berkay Ozcelik Degradable hydrogel systems for biomedical applications , 2016 .

[136]  Juliane Junker,et al.  Interpenetrating Polymer Networks And Related Materials , 2016 .

[137]  S. Imazato,et al.  Effectiveness of non-biodegradable poly(2-hydroxyethyl methacrylate)-based hydrogel particles as a fibroblast growth factor-2 releasing carrier. , 2015, Dental materials : official publication of the Academy of Dental Materials.

[138]  Ellis Meng,et al.  Materials for microfabricated implantable devices: a review. , 2015, Lab on a chip.

[139]  Zheng Zhou,et al.  A high water-content and high elastic dual-responsive polyurethane hydrogel for drug delivery. , 2015, Journal of materials chemistry. B.

[140]  E. Cosgriff-Hernandez,et al.  Determination of the in vivo degradation mechanism of PEGDA hydrogels. , 2014, Journal of biomedical materials research. Part A.

[141]  Matsuhiko Nishizawa,et al.  Highly Conductive Stretchable and Biocompatible Electrode–Hydrogel Hybrids for Advanced Tissue Engineering , 2014, Advanced healthcare materials.

[142]  Jiří Michálek,et al.  Macroporous 2-hydroxyethyl methacrylate hydrogels of dual porosity for cell cultivation: morphology, swelling, permeability, and mechanical behavior , 2014, Journal of Polymer Research.

[143]  Hanqing Yu,et al.  Conductive carbon nanotube hydrogel as a bioanode for enhanced microbial electrocatalysis. , 2014, ACS applied materials & interfaces.

[144]  E. Dragan,et al.  Design and applications of interpenetrating polymer network hydrogels. A review , 2014 .

[145]  Sudha J. Devaki,et al.  Electrically conducting silver nanoparticle–polyacrylic acid hydrogel by in situ reduction and polymerization approach , 2014 .

[146]  Jean-Louis Viovy,et al.  A review of microfabrication and hydrogel engineering for micro-organs on chips. , 2014, Biomaterials.

[147]  P. Dubruel,et al.  The 3D printing of gelatin methacrylamide cell-laden tissue-engineered constructs with high cell viability. , 2014, Biomaterials.

[148]  Tsutomu Okuno,et al.  Effects of UV wavelength on cell damages caused by UV irradiation in PC12 cells. , 2013, Journal of photochemistry and photobiology. B, Biology.

[149]  Shaoyi Jiang,et al.  Zwitterionic hydrogels implanted in mice resist the foreign-body reaction , 2013, Nature Biotechnology.

[150]  Zhenan Bao,et al.  Hierarchical nanostructured conducting polymer hydrogel with high electrochemical activity , 2012, Proceedings of the National Academy of Sciences.

[151]  Subbu Venkatraman,et al.  Photopolymerization of cell-encapsulating hydrogels: crosslinking efficiency versus cytotoxicity. , 2012, Acta biomaterialia.

[152]  M. Dittrich,et al.  Pharmaceutically Used Plasticizers , 2012 .

[153]  Matsuhiko Nishizawa,et al.  Conducting Polymer Microelectrodes Anchored to Hydrogel Films. , 2012, ACS macro letters.

[154]  J. Yagüe,et al.  Systematic control of mesh size in hydrogels by initiated chemical vapor deposition , 2012 .

[155]  J. Simon,et al.  Immune responses to implants - a review of the implications for the design of immunomodulatory biomaterials. , 2011, Biomaterials.

[156]  P. Leleux,et al.  Highly Conformable Conducting Polymer Electrodes for In Vivo Recordings , 2011, Advanced materials.

[157]  J M Carmena,et al.  In Vitro and In Vivo Evaluation of PEDOT Microelectrodes for Neural Stimulation and Recording , 2011, IEEE Transactions on Neural Systems and Rehabilitation Engineering.

[158]  R. Borgens,et al.  The effect of an electrically conductive carbon nanotube/collagen composite on neurite outgrowth of PC12 cells. , 2010, Journal of biomedical materials research. Part A.

[159]  Nathaniel S. Hwang,et al.  Porous poly(vinyl alcohol)-alginate gel hybrid construct for neocartilage formation using human nasoseptal cells. , 2010, The Journal of surgical research.

[160]  Jennifer Patterson,et al.  Hyaluronic acid hydrogels with controlled degradation properties for oriented bone regeneration. , 2010, Biomaterials.

[161]  Alexander Kros,et al.  Light controlled protein release from a supramolecular hydrogel. , 2010, Chemical communications.

[162]  Silviya P Zustiak,et al.  Hydrolytically degradable poly(ethylene glycol) hydrogel scaffolds with tunable degradation and mechanical properties. , 2010, Biomacromolecules.

[163]  Ali Khademhosseini,et al.  Controlling the porosity and microarchitecture of hydrogels for tissue engineering. , 2010, Tissue engineering. Part B, Reviews.

[164]  David J Mooney,et al.  Controlled Growth Factor Delivery for Tissue Engineering , 2009, Advanced materials.

[165]  Chaoliang He,et al.  Synthesis of biodegradable thermo- and pH-responsive hydrogels for controlled drug release , 2009 .

[166]  Wim E Hennink,et al.  The effect of photopolymerization on stem cells embedded in hydrogels. , 2009, Biomaterials.

[167]  L. Cauller,et al.  Biocompatible SU-8-Based Microprobes for Recording Neural Spike Signals From Regenerated Peripheral Nerve Fibers , 2008, IEEE Sensors Journal.

[168]  S. Cogan Neural stimulation and recording electrodes. , 2008, Annual review of biomedical engineering.

[169]  David F. Williams On the mechanisms of biocompatibility. , 2008, Biomaterials.

[170]  J. Kopeček,et al.  Hydrogels as smart biomaterials , 2007 .

[171]  O. Aquilina,et al.  A brief history of cardiac pacing , 2006, Images in paediatric cardiology.

[172]  Marcos R. Guilherme,et al.  Synthesis and characterization of pH-responsive hydrogels based on chemically modified Arabic gum polysaccharide , 2006 .

[173]  David C. Martin,et al.  Neuronal cell loss accompanies the brain tissue response to chronically implanted silicon microelectrode arrays , 2005, Experimental Neurology.

[174]  D. Mooney,et al.  Controlling rigidity and degradation of alginate hydrogels via molecular weight distribution. , 2004, Biomacromolecules.

[175]  Polly Matzinger,et al.  Hydrophobicity: an ancient damage-associated molecular pattern that initiates innate immune responses , 2004, Nature Reviews Immunology.

[176]  Sverre Grimnes,et al.  Bioimpedance and Bioelectricity Basics , 2000 .