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

## TL;DR

This study develops a two-layer electrospun fibrous device capable of managing wound exudate and visually signaling infection through pH-responsive color change, offering a promising approach for chronic wound care.

## Contribution

The paper introduces a novel two-layer electrospun system with independent control over exudate management and infection signaling, demonstrating enhanced functionality over single-layer configurations.

## Key findings

- High BTB loading efficiency (>80%) in PMMA-co-MAA fibers.
- Prompt color change at pH > 7 indicating infection.
- Enhanced water uptake and swelling in the PAA layer.

## 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 (up to nearly 2500 wt.%) and swelling index (up to nearly 300 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.

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Source: https://tomesphere.com/paper/1903.06674