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bioRxiv · 10.1101/2024.04.23.590678

Three dimensionally printed microstructured alginate scaffolds for neural tissue engineering

Abstract

The integration of scaffolds, signalling cues, and cellular components is essential in tissue engineering to create an in vivo equivalent environment that supports physiological function. Scaffolds provide mechanical reinforcement for cellular proliferation and differentiation while providing cues that instruct the development of cells during culture. Alginate (Alg) is a versatile biopolymer for scaffold engineering. However, due to a lack of intrinsic cell-binding sites, thus far, Alg must be functionalized for cellular adhesion. Here, we demonstrate proof-of-concept, bioactive additive-free, microstructured Alg (M-Alg) scaffolds for neuron culture. The M-Alg scaffold was formed by introducing tetrapod-shaped ZnO (t-ZnO) microparticles as structural templates in the Alg that were subsequently removed. These transparent, porous, additive-free Alg-based scaffolds with neuron affinity are promising for neuroregenerative and organoid- related research. HighlightsTetrapod-shaped ZnO (t-ZnO) microparticles are used as a template for the fabrication of open interconnected channels and textured surfaces in 3D printed microstructured alginate (M-Alg) scaffolds. Primary mouse cortical neurons seeded on the 3D printed M-Alg scaffolds show improved adhesion and maturation with extensive neural projections forming inside the scaffolds.

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Li, J., Hietel, B., Brunk, M. G. K., Reimers, A., Willems, C., Groth, T., Cynis, H., Adelung, R., Schutt, F., Sacher, W. D., Poon, J. K. S.. 2024-04-26. Three dimensionally printed microstructured alginate scaffolds for neural tissue engineering. https://doi.org/10.1101/2024.04.23.590678

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