Development and evaluation of chitosan–polydimethylsiloxane–sulfathiazole patches for enhanced wound healing and antibacterial performance

Abstract

Injuries are common in daily life and may result in severe complications if not properly treated. In recent years, extensive efforts have been devoted to developing effective wound dressings that reduce infection risk and accelerate the healing process.In this study, a novel polymeric wound dressing patch was fabricated by integrating sulfathiazole (SF), an antimicrobial agent, into a chitosan (CS) and polydimethylsiloxane (PDMS) matrix using the solvent casting technique. Two different concentrations of SF, 10% and 20% relative to the weight of CS, were used. The chemical structure of the prepared patches was confirmed using Fourier Transform Infrared Spectroscopy (FT-IR), which revealed characteristic peaks for CS, PDMS, and SF. Scanning Electron Microscopy (SEM) images showed a uniform and smooth surface for the CS–PDMS blend, while SF-loaded patches exhibited even dispersion of the drug within the polymeric matrix. Thermogravimetric analysis (TGA) demonstrated that blending PDMS with CS enhanced thermal stability; however, the incorporation of SF slightly reduced this stability. Mechanical testing indicated that the CS–PDMS patch had improved tensile strength and elongation at break compared to CS alone, whereas these properties decreased upon SF incorporation. In the animal experiment, the SF-loaded CS–PDMS patch containing 20% SF demonstrated a significantly greater wound size reduction (83.1%) compared to the control group. These findings were further confirmed by histological analysis. Moreover, the patch exhibited strong antimicrobial activity against a wide range of pathogens, including Escherichia coli, Staphylococcus aureus (ATCC), Candida albicans (ATCC), Aspergillus flavus (clinical isolate), and methicillin-resistant Staphylococcus aureus (MRSA). These findings suggest that the CS–PDMS–SF patch is a promising multifunctional wound dressing with both healing-promoting and antimicrobial properties.