T. Basak, J. L. Shamshina
Texas Tech University,
United States
Keywords: Tissue engineering, chitin, scaffolds, porousness
Summary:
To meet the increasing demand for customized scaffolds in tissue engineering, it's essential to grow human tissues outside the body mirroring the complex structure of the extracellular matrix (ECM). These scaffolds, usually complex three-dimensional porous structures, provide the essential framework for cells to attach and grow into tissues. In cellular agriculture, the biomaterial composing a scaffold plays a crucial role in determining its subsequent characteristics. Chitin is successfully used in creating scaffolding matrices for tissue engineering. To produce TE materials, scaffolds need to meet three main criteria: facilitating cell adhesion and growth, possessing suitable mechanical properties, and being biodegradable. Chitin-based materials fulfill these requirements by promoting cell attachment and development while also being capable of blending with other polymers like collagen or fibrin to closely mimic natural tissue. The effectiveness of artificial scaffolds relies heavily on ensuring sufficient cellular migration throughout the stages of cell growth to achieve uniform cell distribution and interconnection. Therefore, chitinous scaffolds need to exhibit open interconnected networks with consistent architecture and micrometer-scale porosity to facilitate cell invasion and migration. The overall porosity, interconnectivity, and pore size are critical factors influencing cell survival, proliferation, migration, and nutrient diffusion. Despite existing preparations of chitin scaffolds, research in this domain often yields inconsistent results. Our efforts are directed towards the intricate correlation between microstructure and properties in chitin-based tissue engineering constructs. Through experimentation, we aim to understand how various parameters, such as chitin content and type, influence the porousness, pore size, and other microarchitectural aspects of these constructs. We meticulously analyze factors including the crystalline form of chitin (macro-, micro-, or nano-), molecular weight (high, low, nano), solvent composition, crosslinkers, porogens, and drying techniques. We explore techniques ranging from supercritical CO2-drying to lyophilization at different freezing temperatures to engineer chitin scaffolds with tailored characteristics suitable for a wide range of tissue engineering applications.