Preparation and characterization of 4-nitrochalcone-folic acid-poly(methyl methacrylate) nanocapsules and cytotoxic activity on HeLa and NIH3T3 cells

Chalcones of natural origin are plant metabolites which have been explored because of the cytotoxic effects towards tumor cells. In this study, the synthetic chalcone 4-nitrochalcone (4NC) and its encapsulated form in folic acid-poly(methyl methacrylate) (PMMA) nanocapsules (4NC-FA-PMMA) were investigated towards the cytotoxic effects on erytrocytes, mouse embryonic fibroblasts cells (NIH3T3), and tumor cells (HeLa cells). Characterization of 4NC-FA-PMMA presented spherical morphology with nanocapsule-type structure, a mean size of 170 +/- 6 nm, a negative zeta potential of (- 40 +/- 4 mV), and an entrapment efficiency of similar to 80%. In HeLa cells, 4NC induced a dose-dependent reduction in cell viability, with an IC50 value of 46.7 mu M. The cytotoxicity was confirmed by morphological alterations, cell death, and an increase in the population of hypodiploid cells. When 4NC-FA-PMMA nanocapsules were employed at concentrations of 15 and 30 mu M the reduction in cell viability was higher than that of 4NC. In addition, 4NC and 4NC-FA-PMMA nanocapsules did not present any cytotoxic effect on the NIH3T3 cells and human erythrocytes up to 50 mu M. These results demonstrated that the 4NC encapsulation in PMMA nanocapsules with folic acid-modified surface is a better system to promote selective cytotoxic effects to HeLa cells. Therefore, this formulation could be considered a promising preparation with potential chemotherapeutic action.