Biodegradable Janus Electrospun Dressing with Unidirectional Moisture Transport and pH-Responsive Colorimetric...

Large-area wounds, such as burns, extensive trauma, and chronic nonhealing ulcers, present significant clinical challenges due to excessive exudation, high infection susceptibility, and the risk of secondary injury caused by frequent dressing removal for status inspection. These challenges necessitate advanced dressing materials that integrate efficient exudate management with real-time wound monitoring. In response, this study presents a fully biodegradable bilayer Janus electrospun dressing fabricated via layer-by-layer electrospinning. The dressing comprises a hydrophobic poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/polylactic acid (PHBV/PLA) drainage layer for direct skin contact, coupled with a hydrophilic cellulose acetate/epigallocatechin-3-gallate/red cabbage anthocyanin (CA/EGCG/RCA) layer for exudate absorption. The resulting membranes were systematically characterized for morphology (SEM), wettability, mechanical properties, air permeability, and swelling behavior. Antibacterial assays demonstrated inhibition rates of 90% and 92% against Escherichia coli and Staphylococcus aureus, respectively. Furthermore, in vitro cytocompatibility assays confirmed superior biocompatibility, with L929 fibroblast viability exceeding 92%. Notably, the dressing functions as a biosensor for wound pH evaluation via a Python-based RGB algorithm that analyzes the exponential relationships between R/B and R/G color coordinates, providing critical guidance for clinical decision-making. Overall, the biodegradable PPCER Janus membrane offers a sustainable and intelligent strategy for large-area wound management by synergyizing antibacterial, antioxidant, and unidirectional moisture transport functionalities.