Solubilização e estudo citotóxico do lapachol em soluções micelares de misturas binárias (F127/E65S9E65)

Abstract

Lapachol is a bioactive with several activities, known for its anticancer action, but has low solubility in water which makes it difficult to use, may be more effective therapeutically. The use of copolymers for drug solubilisation in water solution is being studied for its efficiency in the dilution and biocompatibility process. The objective of this work is to investigate the copolymers F127, E65S9E65­ and their mixtures regarding their ability to solubilise the bioactive lapachol, release profile and cytotoxicity. Solubility was estimated by UV-Vis. The pure copolymers and their mixtures were characterized by infrared (FT-IR), X-ray, DSC, particle size and dynamic light scattering (Zetasizer). Lapachol was characterized by FT-IR, DSC, NMR. The antioxidant and inhibitory activities of the acetylcholinesterase enzyme were also investigated, as well as the cytotoxic assay using cancer cells from the S970 system with and without bioactive. The S970 mixture was used, as it presented the best results: greatest solubilisation capacity (Scp), capable of increasing the drug solubility by more than 33 times; low value of critical micelle concentration (cmc); small particle size and polydispersity; in addition to presenting an energetically favorable solubilisation process with Gibbs energy values ​​of the solubilisation (ΔG°S) less than zero. The S970LA system showed antioxidant activity, inhibition of the enzyme acetylcholinesterase and toxicity to cell lines of prostate, colorectal and leukemia cancer, in addition to the ability to delay the release of lapachol, presenting Super Case-II transport release mechanism. Thus, the system is promising for carrying lapachol and to assist in the treatment of various diseases such as cancer.