RESUMO
We report here the intercalation of 5-fluorouracil (5-FU), an anticancer drug in interlayer gallery of Na(+) clay (Montmorillonite, MMT), with the assistance of biopolymer (chitosan, CS). The X-ray diffraction patterns, thermal and spectroscopic analyses indicated the drug intercalation into the clay interlayer space in support of CS and stabilized in the longitudinal monolayer by electrostatic interaction. In vitro drug release showed controlled release pattern. The genotoxic effect of drug was in vitro evaluated in human lymphocyte cell culture by comet assay, and results indicated significant reduction in DNA damage when drug was intercalated with clay and formulated in composites. The results of in vitro cell viability assay in cancer cells pointed at decreased toxicity of drug when encapsulated in Na(+)-clay plates than the pristine drug. In vivo pharmacokinetics, biodistribution, hepatotoxicity markers, e.g., SGPT and SGOT, and liver/testicular histology in rats showed plasma/tissue drug levels were within therapeutic window as compared to pristine drug. Therefore, drug-clay hybrid and composites can be of considerable value in chemotherapy of cancer with reduced side effects.