Two-layer Electrospun System Enabling Wound Exudate Management and Visual Infection Response.

Mohamed Bazbouz,Giuseppe Tronci

doi:10.3390/s19050991

Mohamed Bazbouz, Giuseppe Tronci

Open Access

https://doi.org/10.3390/s19050991

Copy DOI

Abstract

The spread of antimicrobial resistance calls for chronic wound management devices that can engage with the wound exudate and signal infection by prompt visual effects. Here, the manufacture of a two-layer fibrous device with independently-controlled exudate management capability and visual infection responsivity was investigated by sequential free surface electrospinning of poly(methyl methacrylate-co-methacrylic acid) (PMMA-co-MAA) and poly(acrylic acid) (PAA). By selecting wound pH as infection indicator, PMMA-co-MAA fibres were encapsulated with halochromic bromothymol blue (BTB) to trigger colour changes at infection-induced alkaline pH. Likewise, the exudate management capability was integrated via the synthesis of a thermally-crosslinked network in electrospun PAA layer. PMMA-co-MAA fibres revealed high BTB loading efficiency (>80 wt.%) and demonstrated prompt colour change and selective dye release at infected-like media (pH > 7). The synthesis of the thermally-crosslinked PAA network successfully enabled high water uptake (WU = 1291 ± 48 − 2369 ± 34 wt.%) and swelling index (SI = 272 ± 4 − 285 ± 3 a.%), in contrast to electrospun PAA controls. This dual device functionality was lost when the same building blocks were configured in a single-layer mesh of core-shell fibres, whereby significant BTB release (~70 wt.%) was measured even at acidic pH. This study therefore demonstrates how the fibrous configuration can be conveniently manipulated to trigger structure-induced functionalities critical to chronic wound management and monitoring.

Highlights

In chronic wounds, such as leg and diabetic foot ulcers, infection requires antibiotic therapy and frequent hospitalisation, and may, in some cases, lead to surgery [1,2,3,4]
A two-layer membrane with integrated exudate management capability and infection responsivity was realised via sequential free surface electrospinning of tetraethylene glycol (TEG)-loaded poly(acrylic acid) (PAA) and bromothymol blue (BTB)-loaded PMMA-co-MAA solutions (Figure 1A)
Fibre loading with halochromic BTB dye in the PMMA-co-MAA layer was expected to equip the resulting membrane with colour change capability following contact with infected exudate

Summary

Introduction

In chronic wounds, such as leg and diabetic foot ulcers, infection requires antibiotic therapy and frequent hospitalisation, and may, in some cases, lead to surgery [1,2,3,4]. Continuous chronic wound monitoring is a promising strategy to enable early detection of infection, aid diagnosis and inform therapeutic decisions [8,9,10]. Reliable wound monitoring devices are still hardly realised, due to the complex infection mechanisms and healing process of these wounds [9]. Aiming at next-generation wound care, multifunctional cost-effective wound management products are needed to support healing in non-self-healing wounds and to signal the occurrence of infection by e.g., visual effects [8]. Multiple wound biomarkers have been reported for wound monitoring, such as pH [11], temperature [12,13], neutrophil extracellular traps (NETs) [14,15], hydrogen peroxide [16,17], lactate [18,19], and wound exudate volume [20], pH monitoring has been reported as one of most

Methods

Results

Conclusion