Design and evaluation of drug-loaded wound dressing having thermoresponsive, adhesive, absorptive and easy peeling properties

In order to develop a novel unique wound dressing, a combination of self-adhesive Eudragit E film with antibacterial drug-loaded poly (N-isopropyl-acrylamide) (PNIPAAm) microgel beads was designed. The result indicates that the tack property of Eudragit E film increased with an increase of the PNIPAAm microgel beads added, but there was no significant difference between the dried PNIPAAm microgel beads with or without adsorbing drug. In addition, the peel strength of Eudragit E film initially decreased with the addition of PNIPAAm microgel beads, but increased to a maximum value when PNIPAAm microgel beads were added from 4% to 7.6%, then decreased again after 7.6%. The optimal concentration of PNIPAAm microgel beads was 7.6% (w/v) which had better tack and peel adhesive properties. The water uptake ratio of Eudragit E film containing PNIPAAm microgel beads was found to be temperature-dependent, suggesting that the Eudragit E film containing PNIPAAm microgel beads enabled to absorb the wound fluid. Eudragit E film containing PNIPAAm microgel beads with or without adsorbing drug had significantly reduced peel strength after 12 h-immersion in solution. All these results suggest that a novel drug-loaded wound dressing has been developed by binding a self-adhesive Eudragit E film with an antibacterial drug-loaded PNIPAAm microgel beads to achieve thermo-responsive, adhesive, absorptive and easy peeling functions.