The anticancer properties of pure
copper (II) acetate and
copper (II) acetylacetonate, alone and loaded on functionalized
sol-gel
titania (TiO(2)), were determined in four different
cancer cell lines (C6, RG2, B16, and U373), using increasing concentrations of these compounds. The
copper complexes were loaded onto the TiO(2) network during its preparation by the solgel process. Once copper-TiO(2) materials were obtained, these were characterized by several physical-chemical techniques. An in vitro
copper complex-release test was developed in an aqueous medium at room temperature and monitored by ultraviolet spectroscopy. The toxic effect of the
copper complexes, alone and loaded on TiO(2), was determined using a cell viability 3(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium
bromide (MTT) assay, when
cancer cells were treated with increasing concentrations (15.75-1000 mg/mL) of these. Characterization studies revealed that the addition of
copper complexes to the TiO(2)
sol-gel network during its preparation, did not generate changes in the molecular structure of the complexes. The surface area, pore volume, and pore diameter were affected by the
copper complex additions and by the crystalline phases obtained. The kinetic profiles of both
copper complexes released indicated two different stages of release: The first one was governed by first-order kinetics and the second was governed by zero-order kinetics. The cell viability assay revealed a cytotoxic effect of
copper complexes, copper-TiO(2), and
cisplatin in a dose-dependent response for all the cell lines; however, the
copper complexes exhibited a better cytotoxic effect than the
cisplatin compound. TiO(2) alone presented a minor cytotoxicity for C6 and B16 cells; however, it did not cause any toxic effect on the RG2 and U373 cells, which indicates its high biocompatibility with these cells.