Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Biopolymeric films based on carboxymethylcellulose combined with sodium alginate or zein are developed as delivery systems for Lithraea brasiliensis essential oil. The matrices improve oil stabilization while maintaining functional film properties. These materials are proposed as promising topical platforms for the treatment of leishmaniasis.

ABSTRACT
This study investigates biopolymeric films based on carboxymethylcellulose combined with sodium alginate polysaccharide or zein protein as matrices for incorporating the essential oil (EO) of Lithraea brasiliensis for potential topical antileishmanial applications. Gas chromatography–mass spectrometry analysis identified 33 constituents in the EO, representing 88.72% of the total oil composition, including myrcene (55.21%), (Z)-nerolidol (8.49%), and β-bisabolenal (7.89%) as the major compounds. FTIR and thermal analyses confirmed the incorporation of the EO into the polymeric matrices and revealed interactions between the oil constituents and the biopolymers. The films were characterized in terms of transparency, ultraviolet-blocking capacity, water vapor transmission rate, and solubility. All films maintained visible-light transmittance while effectively attenuating UV radiation. In vitro assays demonstrate that EO-loaded films exhibit significant antileishmanial activity against Leishmania promastigotes, while their cytocompatibility depended strongly on the polymeric matrix composition. Furthermore, the comparative evaluation of alginate- and zein-containing films revealed that matrix composition significantly influences the physicochemical characteristics and biological performance of the resulting materials. These findings highlight the importance of matrix selection in the design of EO-loaded biopolymeric films and support the potential of CMC-based systems as bioactive platforms for topical applications against leishmaniasis.