Improving anti-hemolytic, antibacterial and wound healing properties of alginate fibrous wound dressings by exchanging counter-cation for infected full-thickness skin wounds.

Nowadays, considerable effort is made to overcome bacterial diseases and combat bacterial resistance. In this context, development of safe and efficient antimicrobial wound dressings which can selectively fight against the bacteria and decrease disruption of normal cells such as red blood cells in wound bed is highly required. In this study, a series of ammonium salts of alginate were prepared and the role of different counter-cations including sodium, triethylammonium, tributylammonium and dihexylammonium were examined with respect to antimicrobial efficacy and selectivity as well as fibroblasts viability. We found that many different parameters such as hydrophilicity, linearity and branching structure, molecular weight and charge density can influence the selectivity of ammonium counter-cations. In vitro biological studies showed that tributylammonium alginate (TBA-Alg) possesses optimum anti-hemolytic and antibacterial properties with less cytotoxicity at 1 mg mL-1 compared with other counter-cations. Furthermore, the fibrous mat of TBA-Alg demonstrated higher swelling ratio and better anti-hemolytic and cytotoxic activities against fibroblasts compared to a commercial silver-impregnated calcium alginate wound dressing. Moreover, histopathological analysis of tributylammonium alginate fibrous mat revealed that this dressing accelerates reepithelialization of infected full-thickness skin wounds as well as the commercial silver-impregnated calcium alginate wound dressing.