Intelligent Wound Dressing for Therapeutic and Diagnostic Management of Wound Infection

Wound infection is a global problem and approximately 13,000 patients with burns required treatment in hospitals in England and Wales every year. Diagnosis of burn infection is problematic and currently diagnosed by clinical observation and judgement. Standard microbiological culture to identify causative pathogens usually take several days. If pathogens present, this will causes tissue damage by further colonization, extensive infection and formation of difficult-to-treat wound biofilm in wounds which inevitably require aggressive antibiotic treatments. Early indication of infection at point-of-care and ability to rapidly distinguish between infected and non-infected states of wound will help in clinical decision making, prevent over-management by inappropriate use of antibiotics, improve patient outcomes and reduce costs of treatment. Here we have develop an intelligent wound dressing that can detect the infection in wounds. The dressing is made of a hydrated agarose film in which the fluorescent dye containing vesicles were mixed with agarose and dispersed within the hydrogel matrix. The release of dye is triggered by interaction of vesicles with virulence factors, secreted in population-density-dependent fashion via quorum sensing, from pathogenic bacteria. Efficacy of dressing was tested with developed static wound biofilm model using clinical strains of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis. The dressing indicated a clear response when in contact with biofilms produced only by pathogenic strains of bacteria. Colorimetric detection on wound biofilms of prevalent pathogens (S. aureus, P. aeruginosa and E. faecalis) is also demonstrated using an ex-vivo porcine skin model of burn wound infection.