Development and characterization of a smart obstetric dressing with a visual indication function.

Abstract

Excessive adhesion between dressings and the wound bed often causes secondary tissue damage and delays healing during dressing removal. This study aimed to develop and evaluate a multifunctional moisture-containing nonwoven dressing composed of silk fibroin protein (SF), polycaprolactone (PCL), and ellagic acid (EA) to improve wound healing while allowing visual assessment of moisture. A composite nonwoven fabric integrating SF, PCL, and EA was fabricated and characterized using spectroscopic analysis to evaluate its fluorescence properties. In vitro cytocompatibility was assessed in the four fibroblast cell lines using cell viability assays. In vivo wound-healing efficacy was investigated in an animal model, and histological evaluation was performed using Masson's trichrome staining and histomorphometric analysis. Spectroscopic measurements indicated that SF and EA synergistically produced bright blue-violet fluorescence under UV illumination, with the fluorescence intensity increasing proportionally to the SF concentration. Cytocompatibility assays confirmed excellent biocompatibility, with all treatment groups maintaining >80% cell viability and the indicator fabric alone exceeding 100%. In vivo studies revealed that both the SF-based indicator fabric and the EA-integrated dressing significantly accelerated re-epithelialization and dermal remodeling compared to a commercial hydrogel control. Histological analysis revealed denser collagen deposition and increased neovascularization in the SF-treated wounds. The SF/PCL/EA moisture-indicating dressing demonstrated dual functionality by serving as an effective visual indicator of exudate and promoting tissue repair. This composite dressing provides both therapeutic and diagnostic benefits for advanced wound-care applications.