Spontaneously formed
hydrogels are attracting increasing interest as
injectable or
wound dressing materials because they do not require additional reactions or toxic
crosslinking reagents. Highly valuable properties such as low viscosity before external application, adequate filmogenic capacity, rapid gelation and
tissue adhesion are required in order to use them for those therapeutic applications. In addition, biocompatibility and biodegradability are also mandatory. Accordingly,
biopolymers, such as
hyaluronic acid (HA) and
chitosan (CHI), that have shown great potential for wound healing applications are excellent candidates due to their unique physiochemical and
biological properties, such as moisturizing and antimicrobial ability, respectively. In this study, both
biopolymers were modified by covalent anchoring of
catechol groups, and the obtained
hydrogels were characterized by studying, in particular, their tissue adhesiveness and film forming capacity for potential skin wound healing applications. Tissue adhesiveness was related to o-
quinone formation over time and monitored by visible spectroscopy. Consequently, an opposite effect was observed for both
polysaccharides. As gelation advances for HA-CA, it becomes more adhesive, while competitive reactions of
quinone in CHI-CA slow down tissue adhesiveness and induce a detriment of the filmogenic properties.