Chitosan associated with chlorhexidine in gel form: Synthesis, characterization and healing wounds applications

Abstract Chitosan has chemical properties that allow the formation of gels in acid media, which can be used as a dressing for wound treatment, since they are biocompatible and have activity against pathogenic microorganisms. Thus, a chitosan gel associated with chlorhexidine was developed and characterized for the study of antibacterial and healing activity. The gels were synthesized by the reaction of the acetic acid solution with chitosan, followed by the addition of 2 and 4% chlorhexidine to the amount of the acid solution being characterized by thermogravimetry, differential scanning calorimetry and infrared spectroscopy, which proved the presence of substances, in the gel. Tests of direct contact with the strain Staphylococcus aureus showed 100% inhibition of bacterial growth and formation of a halo for the associated gels. Histological examination revealed healing on 14th day when animals was treated with chitosan hydrogel containing 2% chlorhexidine, showing a greater contraction power of the wound when compared to the control groups. For the other products tested, healing was better after the 14th day, and except for saline and 4% chlorhexidine groups, all other lesions were closed on the 14th day. The results indicate that a promising material was obtained for use as a healing agent.