This work describes the enzymatic synthesis of multifunctional hydrogels for chronic wound treatment using thiolated chitosan and the natural polyphenol chicoric acid. Gelation was achieved by laccase-catalyzed oxidation of chicoric acid, a natural compound used for the first time as a homobifunctional crosslinker, reacting subsequently with nucleophilic thiol and amino groups from the chitosan derivative. This approach allowed for twice-faster gelation at three-fold reduced crosslinking reagent concentration, compared to reported enzymatic synthesis of hydrogels using gallic acid as a phenolic provider. Hydrogels with 600 % swelling capacity, coupled to only 20 % weight loss after 6 days in physiological conditions, were obtained. The clinically relevant gram-positive Staphylococcus aureus and the gram-negative Pseudomonas aeruginosa, were reduced by up to 4.5 and 5.5 logs, respectively. A tunable, in the range of 20 - 95 %, ex-vivo inhibition of myeloperoxidase (MPO) activity in chronic wound exudate was achieved, together with control over the total matrix metalloproteinases (MMPs) activities.

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