Lapachol-loaded triblock copoly(oxyalkylene)s micelles: Potential use for anticancer treatment

Abstract The use of copolymeric micelles of copoly(oxyalkylene)s for dissolution of poorly soluble bioactive compounds has been studied due to their efficiency in the blood dilution process and biocompatibility. In this study we investigated the use of micellar system of copolymers F127, EO65SO9EO65 (EO = ethylene oxide/SO = styrene oxide) and the binary mixtures of these copolymers for the solubilization of lapachol. Solubility was estimated by UV–Vis. The samples, with and without drug, were characterized by X-ray, DSC, particle size and zeta potential. The antioxidant activity, the cytotoxicity and the release assay for the system SO970(blend of EO65SO9EO65/F127 in the proportions 70/30) were also investigated. The SO970LA system presented the best solubilization capacity (Scp) value. It showed antioxidant activity, a prolonged release time, non-toxic with LC50 > 1000 and a cytotoxic effect on cancer cells. Results showed IC50 values starting at 5.8 μg mL−1 for the free lapachol and 12.3 μg mL−1 for the lapachol-loaded. Therefore, the system presents a potential for anticancer application.