Dressings play a crucial role in wound treatment, providing mechanical protection, stimulating cell proliferation, absorbing exudates and promoting antimicrobial effects. Ellagic acid (EA) has gained great interest in view of its remarkable biological potential, including: antimicrobial, antioxidant, anti-inflammatory and healing properties. This paper aimed to develop sponges of poly (methyl vinyl ether-co-maleic anhydride) (Gantrez®) and gelatin loaded with EA for the treatment of wounds. Initially, the polymeric blending was tested in order to select the best composition for the incorporation of EA. The formulations were obtained by mixing, homogenization and freeze-drying of the Gantrez®-gelatin dispersions. They were submitted to physicochemical, functional and antimicrobial evaluations. The FTIR spectra of the blank sponges showed the formation of amide bands at ∼1644 cm−1, upon the condensation between the amino groups of gelatin and the -COOH found in maleic acids of Gantrez®. The sponges presented an average thickness between 1.7 and 2.7 mm, homogeneous aspect, adequate strength and hydrophilic surface, with contact angles between 51.6 and 62.2°. At 25°C, the samples exhibited bioadhesive properties and gained malleability when submerged in water. The EA-loaded sponges showed water sorption levels ranging between 300 and 500% (in contrast to 100–200% found in the blank sponges), showcasing a significant increment in the swelling capacity after the incorporation of EA. Moreover, their solubility in aqueous medium was limited to 20–40%. Scanning electron microscopy images unveiled microporous structures in the blank sponges, while the loaded sponges exhibited denser and more uniform microstructures. Loaded formulations showed a release of EA between 30.31 and 42.71% after 120h, together with a corelated antimicrobial activity in the ex-vivo wound model against Staphylococcus aureus and Pseudomonas aeruginosa, reducing the bacterial viability in more than 2 logs. Therefore, the Gantrez®-gelatin sponges exhibited favorable functional properties and were found adequate for the incorporation and release of EA. Accordingly, they could be addressed as platforms for wound dressings and a promising approach for wound treatment.
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