Antibacterial Efficacy Testing of a Bioelectric Wound Dressing Against Clinical Wound Pathogens

Abstract

Silver-based wound dressings have been developed for the control of bioburden in wounds. However, the popularity and extensive use of silver-based dressings has been associated with emerging microbial resistances to silver. In this study we examined in vitro antibacterial efficacy of a bioelectric dressing containing silver and zinc against various wound pathogens. Antibiotic-sensitive clinical wound isolates showed a 100% reduction in bacterial growth, except that Enterococcus faecalis isolate was shown to survive with a bacterial log10 reduction rate of less than 102 CFU. We also investigated antibacterial efficacy against the extended spectrum β-lactamase (ESBL) bacteria, multidrug-resistant (MDR) bacteria, and methicillin-resistant Staphylococcus aureus (MRSA). The bioelectric dressing was effective in killing wound pathogens including ESBL, MDR, and MRSA in vitro. Furthermore, based on the primary results against E. faecalis, we carried out extensive studies against several nosocomial Enterococcus species including vancomycin-resistant species. Overall, the vancomycin-sensitive or -resistant Enterococcus species were resistant to this dressing at up to 48 h, except for the vancomycin-resistant Enterococcus raffinosus isolate only showing a 100% bacterial reduction at 48 h, but not at 24 h. The results demonstrated the effective bactericidal activity of a bioelectric dressing against antibiotic-sensitive and MDR strains, but Enterococcus species are bacteriostatic.

Nature's Electric Potential: A Systematic Review of the Role of Bioelectricity in Wound Healing and Regenerative Processes in Animals, Humans, and Plants

“…A recent device, a redox-active Ag/Zn bioelectric dressing, increases keratinocyte migration to facilitate wound closure, needs no external power source, conforms to skin topography and can be cut to the size of the wound (Banerjee et al, 2014 ). Similar wireless bioelectric dressings generate a micro-electrical field which may augment the natural electric field of injury following wounding (Kim et al, 2014 ), and have bactericidal activity on numerous wound pathogens including multidrug resistant organisms (Kim et al, 2016 ). In another study in chronic wounds unresponsive to conventional therapies, a bioelectrical signal therapy device generating an AC pulse train with a stochastic (random) signal led to 87% of the wounds undergoing closure (Fraccalvieri et al, 2015 ).…”

Comparison of in vitro antibacterial activity of streptomycin-diclofenac loaded composite biomaterial dressings with commercial silver based antimicrobial wound dressings

“…Many texts refer to bacterial bio-burden greater than 10 5 CFU/mL organisms per gram of tissue as a criterion for infection [3,6]. In this study we used 2×10 5 In previous studies [13,14,15], it has been demonstrated that the concentrations required to kill S. aureus is higher than P. aeruginosa which is time dependent. DLF required higher concentrations to kill the bacteria that are beyond those clinically achievable with antibiotics, implying that DLF on its own could not effectively inhibit P. aeruginosa based infections.…”

“…Persistent infection impairs wound healing causing repeating inflammatory cycle, resulting in chronic wounds [3,4]. Prevention and control of infection have been identified as essential aspects of wound management [5]. Effective management requires reducing exogenous microbial contamination, debridement, using appropriate dressing(s) and administration of topical and systemic broad-spectrum antimicrobial agents [6].…”

Wireless microcurrent-generating antimicrobial wound dressing in primary total knee arthroplasty: a single-center experience

“… 13 In in vitro testing, the MCD was observed to exhibit an electricidal effect in the presence of antibiotic and multidrug resistant clinical wound isolates. 14 MCD demonstrated greater bactericidal activity versus silver and controls in in vitro testing, and effectively killed bacteria tested on in vitro biofilm models. 15 , 16 In in vivo porcine studies, evidence of reduced early wound inflammation was observed along with increased epithelial thickness.…”