Three-Dimensional Printing of High-Content Graphene Scaffolds for Electronic and Biomedical Applications

Abstract

The exceptional properties of graphene enable applications in electronics, optoelectronics, energy storage, and structural composites. Here we demonstrate a 3D printable graphene (3DG) composite consisting of majority graphene and minority polylactide-co-glycolide, a biocompatible elastomer, 3D-printed from a liquid ink. This ink can be utilized under ambient conditions via extrusion-based 3D printing to create graphene structures with features as small as 100 μm composed of as few as two layers (<300 μm thick object) or many hundreds of layers (>10 cm thick object). The resulting 3DG material is mechanically robust and flexible while retaining electrical conductivities greater than 800 S/m, an order of magnitude increase over previously reported 3D-printed carbon materials. In vitro experiments in simple growth medium, in the absence of neurogenic stimuli, reveal that 3DG supports human mesenchymal stem cell (hMSC) adhesion, viability, proliferation, and neurogenic differentiation with significant upregulation of glial and neuronal genes. This coincides with hMSCs adopting highly elongated morphologies with features similar to axons and presynaptic terminals. In vivo experiments indicate that 3DG has promising biocompatibility over the course of at least 30 days. Surgical tests using a human cadaver nerve model also illustrate that 3DG has exceptional handling characteristics and can be intraoperatively manipulated and applied to fine surgical procedures. With this unique set of properties, combined with ease of fabrication, 3DG could be applied toward the design and fabrication of a wide range of functional electronic, biological, and bioelectronic medical and nonmedical devices.

Recent advances in materials and flexible electronics for peripheral nerve interfaces

“…Recent innovations in soft materials processing and microfabrication can produce low-cost and flexible electronic devices. These techniques include advanced photolithography, ink-jet printing, and 3D-printing (Muth et al, 2014;Jakus et al, 2015). While useful for prototyping, many of these approaches present potential challenges in the scalable manufacturing of high-performance electronic devices such as high unit costs, poor reproducibility, and low yields (Macdonald et al, 2014).…”

3D printing nano conductive multi-walled carbon nanotube scaffolds for nerve regeneration

“…Favored by low cost, easy operation, and versatile bioink, various 3D printed scaffolds have been examined in vivo studies to demonstrate its capability as customized implants at medical clinics [6][7][8][9][10][11]. For example, Jakus et al showed that 3D printed graphene structure is flexible and strong enough to be easily sutured to exiting tissue for biomedical applications [11]. Stereolithography (SL) printing is one of the most popular prototyping technologies, which can fabricate multilayered 3D scaffolds through ultravioletvisible polymerization of photocurable resins.…”

Resistivity and Its Anisotropy Characterization of 3D-Printed Acrylonitrile Butadiene Styrene Copolymer (ABS)/Carbon Black (CB) Composites

“…As such, the method is potentially profitable for both scientific research [1] and commercial manufacturing [2]. With its rapid development in recent years, 3D printing has evolved from manufacturing prototypes to building functional components in numerous fields, ranging from mechanical engineering [3] and biomedical engineering [4][5][6], to electrochemical studies [7]. For applications in various fields, developing and characterizing printable materials with desired properties are currently key areas of research and development.…”