Bacteria-triggered release of a potent biocide from core-shell polyhydroxyalkanoate (PHA)-based nanofibers for wound dressing application

Abstract

Bacterial infection is a serious issue in wound healing. Extensive use of biocides in wound dressings have raised concerns like biocide resistance and unwanted harm to normal skin cells. In this thesis, I report a new approach to realize bacteria-triggered release of biocide to the sites of bacterial infections from core-shell polyhydroxyalkanoate (PHA)-based nanofibers prepared by coaxial electrospinning. The hydrophobic PHA-based shell can effectively prevent the biocide from undesirable payload release in physiological environments without pathogens. However, in the presence of pathogens, the PHA-based shell is degraded by pathogens, and the encapsulated biocide is released. The released biocide subsequently can impose targeted antimicrobial effects on the bacteria. Using Pseudomonas aeruginosa as a model bacterium and dodecyltrimethylammonium chloride as a model biocide, we demonstrated that the core-shell PHA-based nanofibers released encapsulated dodecyltrimethylammonium chloride in the presence of Pseudomonas aeruginosa, resulting in targeted inhibition of Pseudomonas aeruginosa growth.