Developing talin-based shock absorbing materials

Shock absorbing materials are essential for a range of applications. The military and police force require ballistic armour for the protection of their personnel, whilst the aerospace industry require materials that enable the capture, preservation and study of high velocity projectiles. However, the industry standard materials employed for these purposes each display several inherent limitations, including low durability and alteration of the projectiles structure following capture. Protein-based shock absorbing materials, specifically in the form of hydrogels, directly mitigate the limitations of the industry standard materials used for these purposes, with potential for high durability and endothermic mechanisms of energy dissipation. Despite these promising attributes, research to date conducted on protein-based shock absorbing hydrogels has solely focused on biomedical applications. Here, the mechanosensory protein talin was selected as a protein monomer unit for the development of talin- based shock absorbing materials (TSAMs). Talin can undergo repeated force induced unfolding/refolding cycles, dissipating energy in the process through the endothermic mechanism of protein unfolding. Therefore, talin presents as the perfect monomer unit for the development of a shock absorbing hydrogel. Following extensive investigation into the formation and characterisation of the resulting TSAM, experiments were conducted to elucidate TSAMs performance as a high velocity projectile capture and preservation material. When subjected to impacts of 1.5 km/s, the TSAMs were shown to successfully capture and preserve basalt projectiles and aluminium shrapnel, revealing an industrial application for the material outside of the biomedical sector. Due to the inherent attributes of TSAMs incurred from the talin monomer unit, this material presents many advantages over the aerogel materials employed as the industry standard for these experiments. With additional preliminary studies into the scalability and tunability of the TSAMs conducted within this project, this work defined a novel application for protein-based shock absorbing hydrogels with great commercial potential.