Design and Characterization of Secondary and Tertiary Layers of a Multilayer Wound Dressing System

Abstract

Abstract A nonwoven secondary layer was produced from silk fibroin by a compression and spunlacing method. Super absorbent polymer (SAP) was added to the nonwoven mat to increase the exudates and absorption capacity and manage the moisture in the wound site. Three types of tertiary layers, viz., cotton gauze cloth, adhesive tape, and polyurethane film, were experimented on for the properties that are essential for those layers. The structural stability was found to be better in the spunlaced nonwoven compared to the compressed nonwoven. The Phosphate Buffer Saline (PBS) absorption of the nonwoven increased with an increase in the concentration of SAP percentage. The PBS absorption was found to be lower for the spunlaced nonwoven because of the higher fiber entanglement and packing compared to that of the compressed nonwoven. The vapor permeation rate (grams per square meter a day) across the nonwoven mat decreased with an increase in grams per square meter, and there was no effect from the SAP percentage added to the nonwoven mats. Horizontal and vertical wicking of the spunlaced nonwoven was better than that of the compressed nonwoven. The results showed that spunlaced nonwoven would be a better material for the secondary layer. The vapor transmission rate was highest for cotton gauze cloth, followed by adhesive tape and film. The multilayer wound-dressing system consisting of primary, secondary, and tertiary layers was tested for PBS vapor transmission rate and bacterial penetration. The results showed that the wound-dressing system made from film and adhesive tape did not allow the Staphylococcus aureus bacterial culture to penetrate through the wound-dressing system.