Printed Electroceutical Dressings for the Inhibition of Biofilms and Treatment of Chronic Wounds

Abstract

We report on an innovative, fabric-based conformable, and easily fabricated electroceutical wound dressing that inhibits bacterial biofilm infections and shows significant promise for healing chronic wounds. Cyclic voltammetry demonstrates the ability of the electroceutical to produce reactive oxygen species, primarily HOCl that is responsible for bacterial inhibition. In vitro investigation with the lawn biofilm grown on a soft tissue mimic assay shows the efficacy of the dressing against both gram-positive and gram-negative bacteria in the biofilm form. In vivo, the printed electroceutical dressing was utilized as an intervention treatment for a canine subject with a non-healing wound due to a year-long persistent polymicrobial infection. The clinical case study with the canine subject exhibited the applicability in a clinical setting with the results showing infection inhibition within 11 days of initial treatment. This printed electroceutical dressing was integrated with a Bluetooth® enabled circuit allowing remote monitoring of the current flow within the wound bed. The potential to monitor wounds remotely in real-time with a Bluetooth® enabled circuit proposes a new physical biomarker for management of infected, chronic wounds.

Electroceutical treatment of infected chronic wounds in a dog and a cat

“…The PED fabrication and its safe use have been previously reported. 30,36 Briefly, the fabric-based PED was constructed by screen-printing medically compatible Ag/ AgCl ink (Creative Materials #113-09) onto a habotai silk substrate (Figure 1A). 30 The PED was powered by a 6-V battery with maximum current limited to 600 μA (or 0.6 mA) through a 10-kΩ ballast resistor.…”

“…30,36 Briefly, the fabric-based PED was constructed by screen-printing medically compatible Ag/ AgCl ink (Creative Materials #113-09) onto a habotai silk substrate (Figure 1A). 30 The PED was powered by a 6-V battery with maximum current limited to 600 μA (or 0.6 mA) through a 10-kΩ ballast resistor. Medical tape encapsulates all electrical components while providing an electrical and fluid isolation layer, leaving the printed electrodes and battery pack accessible for use.…”

“…The larger dressings (7.5 Â 7.5 cm) presented an interdigitated electrode layout that maximizes the anode area (Figure 1B,C) for highest bacterial clearance. 29,30 For cat wounds, a smaller PED (1 Â 2 cm) was used with the simplified electrode geometry (Figure 1D,E) to match previously reported in vitro bactericidal effects. 29,31 The laboratory fabricated PEDs needed to be secured to the wound for treatment and the electrodes require a moist environment for proper functioning.…”

“…A punch biopsy of the tissue was performed and submitted for culture and antimicrobial susceptibility after 30,36 the last dressing change. No bacterial growth occurred after this last PED treatment as labeled by the green box in Figure 3.…”

“…However, we have previously reported proof of concept for the feasibility of clinical PED use in dog wounds. 30 The previous report included images of the dog wound but did not provide detailed results for the clinical case. The primary focus was on developing the PED as a dressing with the design, fabrication, systems engineering, in vitro disinfection, and electrochemical characterization of the PED.…”