Abstract

Hybrid Crosslink Hydrogels with Controlled Cell Adhesion for 3D-Bioprinted Wound and Deep Burn Implantable Constructs

Josef Jancár, Professor, Brno University of Technology

Amphiphilic BCPs have attracted a great deal of attention in terms of their ability to form micelles, nanocapsules, nanospheres, core-shell nanoparticles in the size of 10–100 nm, characterized by a core-shell architecture in which the core serves as a reservoir for the incorporation of poorly water soluble drugs; while, the hydrophilic shell provides a protective interface between the core and the external medium. Active substance release can be manipulated by choosing biodegradable polymers with different surface or bulk erosion rates, and external conditions such as pH and temperature changes may function as a switch to trigger drug release. Hierarchical structure can be formed simulating layered skin structure employing various techniques including 3D bioprinting. The modification with itaconic anhydride (ITA) that brings carboxylic functional groups and double bonds to the end of light, temperature and pH sensitive gel forming macromonomers has attracted attention since they can be cross-linked either covalent bonding via rapid photopolymerization and/or physically by hydrogen bond or ionic interactions of carboxylic groups with Ca2+ in order to produce new functionalized 3D-hydrogel network. Moreover, functional –COOH groups can be used as coupling sites for increasing hydrogel’s biocompatibility, bioinductivity, adhesion or other physical properties and thus might be “tailored” for the desired type of biomedical application. We demonstrated that only a small amount of chemical cross-links leads to significant changes in the biomechanical behavior of the hydrogel, thus, providing means to control its ability to adapt and self-heal. We also found that treatment of deep skin wounds and burns can benefit from gradient layer structure constructs which can be advantageously prepared employing 3D bioprinted hydrogel constructs. Patient individualized layered and vascularized constructs can also release bioactive substances and tissue specific cells to accelerate hea