Laboratory Research
Chronic wounds have a prolonged inflammatory phase which hinders the normal wound healing process. These wounds are often colonized by biofilm forming bacteria that can trigger the inflammatory process and elevate levels of matrix metalloproteases. These enzymes often cause tissue damage. A novel wound hydrogel (NWG) has been formulated with metal chelators, an antimicrobial agent, and a non-ionic surfactant to disrupt extra polymeric matrix of biofilm and to enhance inactivation of biofilm embedded microorganisms as well as to inhibit metalloprotease activity. The objectives of this study were to evaluate anti-biofilm activity of NWG, assess anti-metalloprotease activity, and to assess safety.
Methods:
The ability of the NWG to inhibit biofilm formation of Staphylococcus aureus, S. epidermidis, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter bumannii and Candida albicans was tested using colony biofilm assay. The efficacy of the NWG was tested in vitro using colony biofilms of the same organisms. Biofilm data were analysed using one-way ANOVA and post-hoc Tukey test with significance level of P≤0.05. Activity of the NWG against matrix metalloproteases such as collagenase and tumor necrosis factor-alpha converting enzyme (TACE) was tested using commercial kits. The percent inhibition of enzyme activity was calculated. Biocompatibility testing were performed as per ISO 10933 guidelines.
Results:
The NWG inhibited biofilm formation of all tested organisms to below detection limit in 24 h. Biofilm embedded S. aureus, S. epidermidis, E. coli, P. aeruginosa, A. bumannii and C. albicans were significantly (P≤0.05) inactivated by the NWG. Viable numbers of S. aureus, E. coli, A. bumannii and C. albicans decreased by ≥ 6 Log CFU after two 24 h application of the NWG. The NWG inhibited collagenase and TACE activity by 100%. Biocompatibility tests performed as per ISO 10933 showed that product was non-irritating, non-sensitizing, and non-genotoxic at tested conditions. The NWG did not cause any acute systemic toxicity.
Discussion:
The NWG was effective at inhibiting biofilm formation and reducing viable numbers of biofilm embedded test organisms, suggesting that chelators, antimicrobial agent, and surfactant performing their intended roles effectively. Complete inactivation of collagenase and TACE activity showed that formulation could impact matrix metalloproteases. These studies demonstrated that the NWG was effective at inactivating biofilm embedded microorganisms and metalloproteases. Based on biocompatibility test results, composition of the NWG did not cause any negative reactions. Therefore, it is expected that the NWG will improve wound healing by providing moist wound environment that is beneficial to healing of both acute and chronic wounds.
Trademarked Items:
References: