Physical-Chemical Properties and Antioxidant Activity of Pectin-to-Glycerol Film Ratios with Quercetin Added for Wound Dressing Use

Natural-origin polymers in thin film form are promising candidates for dermal wound dressings due to their biocompatibility and ability to incorporate bioactive compounds. This study evaluated the physicochemical properties and antioxidant activity of pectin-to-glycerol films with added quercetin for potential wound dressing applications. Pectin was extracted from Citrus × aurantiifolia bagasse, yielding 15%, with a molar mass of 333,000 g/mol and a 54.1% degree of esterification, classifying it as high-methoxyl pectin. Films were produced via casting using a factorial experimental design. They exhibited homogeneous appearance, with some bubble formation at higher viscosities. Scanning electron microscopy confirmed good quercetin dispersion. Statistical analysis revealed quercetin content significantly influenced thickness, opacity, and water vapor permeability. Mechanical properties, modeled quadratically, showed that both glycerol and quercetin reduced film stiffness. Antioxidant activity exceeded 40%, attributed solely to quercetin. Thermal analysis indicated the presence of pure pectin fractions in high-pectin formulations, correlating with increased stiffness and permeability. Overall, the films demonstrated favorable characteristics for wound healing, with one formulation (F6) showing optimal mechanical, permeability, and antioxidant properties, making it a strong candidate for bioactive wound dressing applications.