In vitro bactericidal efficacy of a new sun- and heat burn gel.

Abstract

We assessed the in vitro bactericidal efficacy of a new sunburn gel (Rescudermtrade mark; RESC) against planktonic and sessile Pseudomonas aeruginosa (PSEUD) and Staphylococcus epidermidis (STAPH). While PSEUD levels were 4log(10) lower than those of STAPH within 24h of adding RESC to contaminated nutrient broths, all bacterial counts were comparable by 48h. PSEUD and STAPH levels were then measured after applying either a single or three consecutive aliquots of RESC to polyurethane sponges. Gel was removed after 5 or 20min, or left on for 72h. Bacterial counts in placebo-treated sponges had plateaued by 24h to values above 9log(10)CFU/mL. In contrast, six out of seven of the RESC application modalities reduced bacterial levels below 4log(10)CFU/mL for 72h. RESC remained effective against STAPH despite up to a 24h treatment delay, irrespective of the number of applications. Repeated RESC applications were required to maintain PSEUD below 4log(10)CFU/mL when the delay exceeded 7h. These data demonstrate the differential susceptibility of planktonic and sessile bacteria to RescuDermtrade mark. This product might be a good candidate for reducing the opportunity for wound infection, especially in burns.