Fabrication of gelatin/silk fibroin/phage nanofiber scaffold effective against multidrug resistant Pseudomonas aeruginosa

Abstract

Objective The alarming rise of multi-drug resistant (MDR) Pseudomonas aeruginosa has prompted the World Health Organization to consider it a serious threat to human health. Although phage (Phg), an effective antibacterial treatment option, can maintain long-term infectivity via lyophilized storage, freeze-drying can be expensive and time-consuming. Thus, we propose electrospun gelatin/fibroin (G/F) nanofibrous formulation for dehydrating and storing phage against MDR P. aeruginosa. Significance The formulation of phage within the nanofibrous structure of the electrospun G/F scaffold would result in antimicrobial activity against MDR P. aeruginosa leading to enhanced wound healing. Methods Phg effective against MDR P. aeruginosa was isolated, characterized and loaded within G/F nanofibers by electrospinning. Morphology, crystallinity and thermal stability as well as the antimicrobial activity and the biocompatibility of the developed G/F/Phg nanofibers were determined. Results Phg-loaded G/F nanofibers revealed an amorphous structure with good thermal stability at temperatures below 300 °C and exhibited effective antibacterial activity against MDR P. aeruginosa with ∼2 log reduction in the bacterial count which increased to ∼4 log reduction in bacterial count after 16 h as compared to both the G/F nanofibers and the negative control. Lack of cytotoxic effects on cultured fibroblasts supported the biocompatibility of G/F/Phg nanofibers. Conclusion The developed G/F/Phg nanofibers are able to maintain the viability of phage and represent a promising antimicrobial dressing for wounds infected with MDR P. aeruginosa.