Scaffold‐guided formation of neuronal‐like networks, especially under electrical stimulation, can be an appealing avenue toward functional restoration of injured nervous systems. Here, 3D conductive scaffolds are fabricated based on printed microfiber constructs using near‐field electrostatic printing (NFEP) and graphene oxide (GO) coating. Various microfiber patterns are obtained from poly(
Integration of conductive electrodes with 3D tissue models can have great potential for applications in bioelectronics, drug screening, and implantable devices. As conventional electrodes cannot be easily integrated on 3D, polymeric, and biocompatible substrates, alternatives are highly desirable. Graphene offers significant advantages over conventional electrodes due to its mechanical flexibility and robustness, biocompatibility, and electrical properties. However, the transfer of chemical vapor deposition graphene onto millimeter scale 3D structures is challenging using conventional wet graphene transfer methods with a rigid poly (methyl methacrylate) (PMMA) supportive layer. Here, a biocompatible 3D graphene transfer method onto 3D printed structure using a soft poly ethylene glycol diacrylate (PEGDA) supportive layer to integrate the graphene layer with a 3D engineered ring of skeletal muscle tissue is reported. The use of softer PEGDA supportive layer, with a 105times lower Young's modulus compared to PMMA, results in conformal integration of the graphene with 3D printed pillars and allows electrical stimulation and actuation of the muscle ring with various applied voltages and frequencies. The graphene integration method can be applied to many 3D tissue models and be used as a platform for electrical interfaces to 3D biological tissue system.
more » « less- NSF-PAR ID:
- 10457887
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Healthcare Materials
- Volume:
- 9
- Issue:
- 4
- ISSN:
- 2192-2640
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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