Physicochemical characterization of functionalized-nanostructured-titania as a carrier of copper complexes for cancer treatment

In the present paper we report the preparation and characterization of functionalized-TiO2 (F-TiO2) to obtain a biocompatible material to be used as carrier of alternative anticancer agents: copper acetate and copper acetylacetonate. The sol-gel procedure was used to prepare the fuctionalized titania material through hydrolysis and condensation of the titanium's butoxide. Sulfate, amine and phosphate ions served as functional groups which were anchored to the titania's surface. Mineral acids and gamma amine butyric acid were the precursors and they were added at the initial step of the synthesis. The copper complexes were loaded on titania and were also added to the reactor synthesis from the beginning. Infrared and ultraviolet-visible spectroscopies were the principal techniques used to the characterization of F-TiO2 and copper complexes loaded on titania materials. Transmission Electronic Microscopy (TEM) was used to complement the characterization's studies. The biocompatibility of F-TiO2 was evaluated by treating different cancer cell lines with increased concentration of this compound. The amine, the sulfate and the phosphate on the titania's surface, as well as the integral structures of the metal complexes on titania were well identified by infrared and ultraviolet-visible spectroscopies. The TEM photographs of Cu(acac)(2)/F-TiO2 and Cu(Oac)(2)/F-TiO2 materials showed the formation of nanoparticles, which have sizes ranging from 4 to 10 nm, with no morphology alterations in comparison with F-TiO2 nanoparticles, suggesting that the presence of low quantities of copper do not affect the structure of the nanoparticles. The Energy Dispersive Spectroscopy (EDS) confirms the presence of copper on the titania's nanoparticles. The biological results indicate that there is more than 90% cell survival, thus suggesting that F-TiO2 does not cause damage to the cells. Therefore, highly biocompatible titania was obtained by functionalizing its surface with those ions which in a certain way are similar to the hydrophilic heads of phospholipids in the double layer of the cell membrane. (C) 2014 Elsevier B.V. All rights reserved.