Researchers at RCSI University of Medicine and Health Sciences and AMBER, the SFI-funded materials research centre based in Trinity College Dublin, have developed a new graphene-based biomaterial with potential for spinal cord tissue regeneration and enhancing recovery in patients with neural injuries.

Spinal cord injuries have serious implications for patients, as available therapies are unable to restore lost neural function. However, in a recent breakthrough supported in part by the IRFU Charitable Trust, RCSI, TCD and AMBER researchers have developed a biomaterial that promotes neuronal growth using nanomaterials and electrical stimulation. The research is published in Applied Materials Today, a leading global academic journal on materials sciences.

The researchers found that combining an electroconductive material with a regenerative natural matrix in a composite new biomaterial allows for the transmission of electrical signals across damaged tissue. This encourages the growth of neurons, thereby restoring lost neural function.

This was achieved by combining the properties of graphene (a highly conductive nanomaterial) and collagen (a protein with known regenerative potential, abundant in the human body, that is capable of supporting cells).

The result of this is a 'biohybrid' material that is softer and more biocompatible than current stimulation materials and has increased electrical conductivity compared to current neuronal growth materials, which is a key element as electrical stimulation promotes growth in neuronal cells.

This research presents a significant step forward, as current treatments for such injuries involve the introduction of neuronal devices composed of foreign materials, typically metals, to the body. This can result in scarring which inhibits proper regeneration of spinal cord tissue and outgrowth of neurons. As collagen is a soft material, it significantly reduces the likelihood of scar tissue formation at these sites, while the graphene flakes interspersed through this scaffold allow for the conduction of electrical signals. It is also inexpensive to produce, lending itself towards being developed as an 'off the shelf' treatment/therapy for repairing neural injuries and other tissue defects.

Another benefit of using graphene as a conductive material is that it can be combined with other polymers to form scaffolds, which are support structures that can be implanted into patients to promote wound healing and tissue regeneration. This is not possible with current metallic implants, which are often limited by the biocompatibility of the metal.

Commenting on the research, Professor Fergal O'Brien, Head of the Tissue Engineering Research Group (TERG) and Professor of Bioengineering & Regenerative Medicine at RCSI said: "The unique interdisciplinary environment provided by AMBER whereby 2D materials from the Coleman group in TCD can be combined with materials from RCSI with proven regenerative potential provides an opportunity for disruptive innovation like this to occur."

Jack Maughan, a PhD student in AMBER working between TCD and RCSI, said: "The novelty of our work arises from it being conductive, biocompatible, processable into a range of different structures, and much softer than traditional electrode materials all at once – this is a tough challenge to solve, and our work represents a large step in the right direction."

This breakthrough has several potential applications outside of neural damage, including cardiac and bone tissue engineering. The study was conducted in the TERG led by Professor Fergal O'Brien in RCSI and the Chemical Physics of Low-Dimensional Nanostructures group led by Professor Jonathan N. Coleman in TCD. It was supported by funding from the IRFU Charitable Trust, SFI AMBER Centre and the Irish Research Council Postgraduate Fellowship program.