Novel composite double-layered dressing with improved mechanical properties and wound recovery for thermosensitive drug, Lactobacillus brevis

Abstract

The objective of this study was to develop a novel composite double-layered dressing (CDD), with improved mechanical properties and wound recovery, to administer the thermosensitive drug Lactobacillus brevis (LB). The system was based on the release of LB to enhance the activation of tissue regeneration in infected wounds. The CDD was composed of an LB-loaded hydrogel top layer with an external hydrocolloid type layer. The LB-loaded hydrogel top layer was prepared by the freeze-thawing method using polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP), thus improving the release properties of LB. The high-temperature melting method was employed to produce the external layer of the dressing, using polyisobutylene (PIB), styrene-isoprene-styrene copolymer (SIS copolymer), paraffin oil, and sodium carboxymethylcellulose (CMC), thus improving mechanical properties. Numerous LB-loaded CDDs were prepared at various ingredient ratios; their swelling and mechanical properties and LB release were assessed. A novel LB-loaded CDD, composed of a PVP/PVA (0.5/10) hydrogel top layer and a PIB/SIS copolymer/paraffin oil/sodium CMC (20/25/12/43) external hydrocolloid membrane, revealed excellent mechanical properties (5.18 × 10−3 ± 2.138 × 10−4 N/mm2, Young's modulus), swelling capacity (801 ± 47%), and drug release (66.7 ± 2.9%, 120 min). Moreover, LB-loaded CDD improved the wound healing efficacy in the P. aeruginosa infected wounds of rats compared to a commercial product and a CDD without LB. The developed novel LB-loaded CDDs were considered an effective treatment for infected wounds and a potential thermosensitive drug carrier, which could improve the efficacy of wound recovery.