Control of invasive Pseudomonas burn wound infection with mafenide acetate electrospun wound dressing

Abstract

Invasive wound infections are a leading cause of mortality in burn patients. Pseudomonas aeruginosa is among the most prevalent organisms associated with invasive burn wound infections. It is most effectively prevented by Sulfamylon® cream. The active compound, mafenide acetate, enters the wound rapidly and achieves the local concentration of 2- to 5- fold above the minimal inhibitory concentration for P. aeruginosa at 1–2 hrs. However, within 8–10 hrs, the mafenide acetate concentration rapidly declines to subinhibitory concentrations, and the treatment needs to be reapplied. In this study, we described the development of an electrospun burn wound dressing that could sustain the treatment effect by continuously releasing mafenide acetate at therapeutic concentrations into burn wounds for ≥ 24 hrs. We demonstrated by scanning electron microscopy that the mafenide acetate electrospun wound dressing consisted of smooth and uniform fibers. The extent and rate of mafenide acetate release from the dressing were determined in vitro using drug release and skin permeation tests and in vivo using a rat burn model. Finally, the mafenide acetate electrospun wound dressing’s antimicrobial activity in vitro and its capability to control invasive Pseudomonas infection in vivo was determined using a modified AATCC 100 test and the modified Walker-Mason scalded rat burn model, respectively.