Development and characterization of a smart wound dressing: collagen membrane with antimicrobial properties and bacterial monitoring

Abstract Burns are severe injuries that can lead to infection and delayed healing, particularly in second-degree burns, where the dermal layer is compromised. Early detection of infection remains a major clinical challenge, as infected wounds typically exhibit a shift from acidic to neutral or alkaline pH. Failure to promptly identify these changes may result in rapid infection progression, delayed healing, and increased risk of complications, highlighting the urgent need for advanced monitoring strategies in wound care. In this context, the development of smart wound dressings capable of real-time pH monitoring is of high clinical relevance. In this study, a smart wound dressing based on collagen (COL) crosslinked with vanillin (VAN) and incorporated with red cabbage extract (RCE) was developed. The crosslinking process was confirmed by FTIR, TGA, DSC, and ¹H NMR analyses, indicating increased crosslinking density, especially at higher VAN concentrations (3%) and in the presence of RCE. Rheological analysis revealed a predominantly elastic behavior (G′ > G″) for all samples. Thermal analysis demonstrated shifts in thermal transitions, confirming structural modifications, while SEM images showed the formation of a three-dimensional crosslinked network. Mechanical analysis indicated improved Young’s modulus for COL/RCE/VAN membranes compared to pure COL. Swelling studies revealed reduced swelling in RCE-containing membranes, while maintaining values above 70%, suitable for exudate absorption. Biological assays confirmed cytocompatibility, with cell viability above 70%. Antimicrobial evaluation demonstrated that COL/VAN 3% and COL/RCE/VAN 3% inhibited bacterial growth, also supported by optical density measurements. Additionally, RCE retained its pH-responsive behavior, enabling visual detection of bacterial activity through color changes. Among the formulations, COL/RCE/VAN 3% showed the best overall performance, highlighting its potential as a smart wound dressing for second-degree burns.