Printable Biodegradable Hydrogel with Self-Crosslinking Agents for Wound Dressings

摘要

The printed Biomaterial Laboratory at UTEP does research a printable hydrogel which can have appropriate properties for tissue engineering of the skin. Skin is the largest organ in our body which protects us from the environment and pathogens. Skin can be affected by burns and also by diabetic foot ulcers. The current tissue engineered skin substitutes for treatment of diabetic foot ulcers have many shortcomings including difficulty of handling, little if any host integration and not being customizable. The goal of this research is to create a wound care material that helps by integrating with the host tissue. We have been investigating a biodegradable hydrogel which is derived from natural proteins and carbohydrates creating a scaffold to use as a substrate to grow cells. The main components of this hydrogel are gelatin and alginate, both materials with very high biocompatibility and promoting cell proliferation and vascularization. Here we have been studying the oxidation of sodium alginate to generate aldehyde groups that can crosslink the amino group of gelatin and form the biodegradable hydrogel. We also have been investigating the viscosity, gelling time and degree of crosslinking of alginate as a function of pH, degree of oxidation, concentration and temperature. Viscosities for 10% alginate solutions in the range of 5-10cp are obtained, making this material printable. For printable testing we modified an inkjet printer to control the temperature of the cartridge and of the deposition plate. In general, control over the concentrations of alginate as well as the spatial dispensing via printing in a temperature-controlled environment should allow us to generate wound dressings of tunable properties. For future work we will include testing viscosity and printability of alginate adding different types of cells, as fibroblast, keratinocytes and endothelial cell, varying cell concentration. We will also include testing the wound dressing in a small animal model on healing and wound contraction.