A collagen wound dressing with silver ion exchanged zeolite based active ingredient and its comparison with commercial dressings

Introduction: Biofilm formation has been reported to cause chronic inflammation and delay healing of wounds, especially chronic and acute dermal wounds. Biofilms formed deep in the wound disrupts healing and is hard to eradicate (1). Current clinical treatment includes cleansing, debridement, refashion and dressing. Developing wound dressings that can destroy biofilms with minimum cytotoxicity is an active product development are. We will present data on a dressing which has a 1) collagen matrix that promotes the transition of the wound to a remodeled, healed state; 2) embedded within this matrix are porous nanozeolite crystals with positively charged surfactant molecules 3) these nanozeolite crystals also encapsulate antimicrobial silver ions (2). We will present data comparing the zeolite-dressing with four of the leading silver-based commercial dressings in their ability to reduce bacterial load of mature Pseudomonas aeruginosa (PA01) biofilms using in vitro colony biofilm assay.Methods:Wound dressings were prepared by deposition of silver-zinc ion-exchanged nanozeolites along with benzalkonium chloride on a commercially available ECM matrix. These dressings and the commercial dressings were introduced on top of a SWF (simulated wound fluid) layer on a 48-hour PA01 biofilm grown on a cellulose membrane resting on a nutrient-loaded agar gel. After well-defined periods of time (1-7 days), the bacteria on the dressing and the cellulose membrane were extracted and the bacterial colonies counted.Results:On the already formed biofilms, the zeolite-encapsulated silver-based nanozeolite dressing performed significantly better (p