Recapitulating the Mechanical Anisotropy of the Spinal Cord via 3D Printing and Sinusoidal Scaffold Design
摘要
The proposed work aims to recapitulate the anisotropic behaviour of the spinal cord through the design of structures with sinusoidal characteristics. This behaviour is considered relevant because neural cells are sensitive to the mechanical environment in which they are located, therefore being a crucial factor to advance and develop strategies to repair the injured spinal cord. To achieve this challenge, a design of experiments was conducted to find the most suitable sinusoids and then develop a structure that recapitulates the anisotropic behaviour of the spinal cord. The rationale for the structure conceptualization took into consideration the printing limitations in terms of sinusoidal features (amplitude and wavelength) as well as the requirements for the spinal cord tissue engineering together with the native tissue properties. Such a structure, after being simulated through the finite element method, was printed using the 3D melt-electrowriting printing technique and was subsequently subjected to tensile tests for validation. Simulations showed longitudinal and transverse elastic moduli of 64 kPa and 24 kPa, respectively, matching the target values for the spinal cord white matter. Experimentally, was observed a longitudinal modulus ranging from 113 to 245 kPa, and the transverse one between 18 and 69 kPa. In this study, is presented the potential of sinusoidal scaffold designs fabricated by melt-electrowriting to recapitulate the mechanical anisotropy of the white matter of the spinal cord.