Development of a cost-effective synthetic model of the rat sciatic nerve for mechanical testing of tissue adhesives

Rodents are widely employed in biomedical research due to their physiological similarity to humans and the availability of established experimental protocols. Among them, the rat sciatic nerve is commonly used as a reference for human peripheral nerves in studies of regeneration, repair, and mechanical characterization. However, rodent peripheral nerves exhibit substantial inter- and intra-specimen variability in their mechanical andstructural properties, complicating reproducibility and comparison across experiments. This limitation becomes particularly relevant in studies involving tissue adhesives, where the mechanical response of the biological substrate can strongly influence the evaluation of adhesive performance and the interpretation of bonded-joint behaviour. To overcome these limitations, synthetic constructs and analytical or numerical models have been proposed to replicate the behaviour of biological tissues. While effective, these approaches often involve complex fabrication processes, high costs, or require extensive prior knowledge of tissue properties, limiting their routine laboratory application. In this study, we propose a simplified, reproducible, and cost-effective synthetic analogue of the rat sciatic nerve that replicates its mechanical behaviour. Different polymers were mechanically characterized via tensile testing and compared with nerve tissue. The best polymer demonstrated an elastic response most closely matching that of biological nerves, while also providing superior tensile strength, which contributes to the mechanical robustness of the synthetic analogue during adhesion testing. Adhesion tests on cyanoacrylate-bonded natural and synthetic specimens showed no statistically significant difference in joint stiffness between bonded PVC and bonded sciatic nerve specimens, although the small sample size limits the strength of this comparison.