When skin is superficially damaged, the wound is rapidly repaired. However, when the injury destroys both epidermis and dermis, patients often die from infection or loss of plasma. If patients survive with the help of skin grafts, the skin regenerates but often heals with the formation of abundant scar tissue without the regeneration of some cell types, including hair follicles and sebaceous glands. Thus, an improved scaffold should release bioactive cytokines to promote healing and cell differentiation. It should also be noted that artificial skin often contains animal material, such as collagen, which may contain infectious material. Due to these problems, there is a need for improved methods and materials for fabricating artificial skin. Unfortunately, there are only a limited number of biocompatible and biodegradable materials available. Hydrogels have been used as an alternate artificial skin, because good hydration is the most important external factor responsible for optimal wound healing, water being necessary for transport of nutrients to the growing cells. Hydrogels, however, are commonly not physically strong enough to mimic the tough, thin dermis.

The polymer system most often used in skin scaffold synthesis is a polyester based on lactic acid (PLA) and glycolic acid (PGA). However, these polyesters have been shown to degrade to their monomeric components, resulting in a high local acidity that can destroy proteins. Thus antacids and sugars have to be added to protect cytokine activity. So a material that avoids acidity would be more useful in the development of a skin scaffold capable of delivering bioactive molecules.

A hydrogel compound made from non-animal materials has been developed with significantly enhanced mechanical strengths and biocompatibilities, while still being biodegradable. The proposed product would be a two-layer hydrogel system with the lower layer comprised of a porous, softer cohesive mixture; and an overlying upper layer which is a dense and stronger mixture of similar composition, thus being compatible. It may be possible to incorporate biological signal proteins to facilitate healing.

Animal testing not yet completed.

File Number: 2009-03 

Disease: Dermatology