Development of a prototype wound dressing technology which can detect and report colonization by pathogenic bacteria

Abstract

A new methodology for detecting the microbiological state of a wound dressing in terms of its colonization with pathogenic bacteria such as Staphylococcus aureus or Pseudomonas aeruginosa has been developed. Here we report how stabilized lipid vesicles containing self-quenched carboxyfluorescein dye are sensitive to lysis only by toxins/virulence factors from P. aeruginosa and S. aureus but not by a non-toxic Escherichia coli species. The development of the stabilized vesicles is discussed and their response to detergent (triton), bacterial toxin (α-hemolysin) and lipases (phospholipase A(2)). Finally, fabrics with stabilized vesicles attached via plasma deposited maleic anhydride coupling are shown visibly responding to S. aureus (MSSA 476) and P. aeruginosa (PAO1) but not E. coli DH5α in a prototype dressing.

Self-reporting hydrogels rapidly differentiate among enterohemorrhagic Escherichia coli (EHEC) and non-virulent Escherichia coli (K12)

“…15,16,17,18 In different strategies, virulence factors secreted by pathogenic bacteria are targeted for the in situ detection. 19,20,21,22 Zakir Hossain et al 23 reported for instance on a lab-onpaper assay for the rapid and sensitive detection of E. coli in water. In this method the reporter 5 elements were printed on a small paper strip.…”

Porous Silicon Resonant Microcavity Biosensor for Matrix Metalloproteinase Detection

“…The deployment of advanced detection technologies, such as diagnostic and theranostic sensors in the wound management, especially for monitoring the healing status of acute and chronic wounds is rapidly growing . The ideal diagnostic tool would afford a clear and simple read‐out, not requiring interpretation from medical expert, while a theranostic would release therapeutics in response to altered wound healing, for instance as a result of bacterial infection . It would be desirable for such diagnostic or theranostic sensors to be incorporated into a wound dressing (a “smart” dressing) or deployed as a point‐of‐care (POC) device that provides fast responsive and is both sensitive and selective.…”

Staphylococcus aureus Interaction with Phospholipid Vesicles – A New Method to Accurately Determine Accessory Gene Regulator (agr) Activity

“…This method is based on the interaction of delta and Phenol Soluble Modulin (PSM) toxins, both used as surrogate markers for RNAIII and RNAII activity respectively, with lipid vesicles containing encapsulated self-quenched fluorescent dye. Recent work in this group has focused on the development of a sensor for bacterial infection in burns [25], [26] which is dependent on toxin-lipid interaction. One fundamental element in the transition from inactive toxin monomers into fully functional membrane-damaging agents is the lipid and protein composition of the target membranes, particularly important in artificial membranes.…”