Nanostructured Dual-Delivery System with Antioxidant and Synergistic Approach for Targeted Dermal Treatment

TL;DR

A new nanofiber-based wound dressing combines antioxidants and antibiotics to fight infection and promote healing.

Contribution

A novel dual-delivery system using PHB-nanofibers and liposomes for targeted release of bioactive agents is first reported.

Findings

The system showed synergistic antimicrobial effects against multiple bacteria with FIC indices of 0.09–0.73.

The highest antimicrobial increase (~73.56%) was observed against Staphylococcus epidermidis.

The dressing retained bioactive properties and supported wound re-epithelisation despite slight immune response stimulation.

Abstract

Biocompatible nanofibrous dressings integrating bioactive compounds with antioxidative and antimicrobial properties offer a promising solution for effective wound healing. In the presented study, we developed a novel dual-delivery system by combining forcespun nanofibres with poly(3-hydroxybutyrate) (PHB)-liposomes to enhance bioavailability and enable targeted release of bioactive agents (eugenol, thymol, curcumin, ampicillin, streptomycin, gentamicin). These agents exhibited notable antioxidant activity (2.27–2.33 mmol TE/g) and synergistic or partially synergistic antimicrobial effects against E. coli, M. luteus, S. epidermidis, and P. aeruginosa ( Fractional Inhibitory Concentration index 0.09–0.73). The most potent combinations, particularly thymol, eugenol, and ampicillin, were encapsulated in the nanofibre–liposomal matrix. The successful preparation of a new combined delivery system was confirmed by structural analysis using Electron and Fluorescence Microscopy. The dual-composite materials retained the antimicrobial properties of the individual compounds upon release, with the highest increases of ~73.56% against S. epidermidis. Cell viability and in vitro immunology assays using the human keratinocyte cell line (HaCaT) showed a slight decrease in viability and immune response stimulation, while not impairing wound re-epithelisation. These findings highlight the potential of firstly reported novel carrier utilising both PHB-nanofibres and PHB-liposomes, exhibiting simultaneous antioxidant and antimicrobial activity as promising candidates for the treatment of infected wounds under oxidative stress.

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