CONICET | Buscador de Institutos y Recursos Humanos

The aim of this work focused on the study of synthetic hydroxyapatite nanoparticles charged with a fluoroquinolone antibiotic, ciprofloxacin (CIP). These nanoparticles were performed following a modification of the method presented for Li et al. (Y. Li et al. Mater. Lett. 56 (2002) 496). Appropriated amounts of CIP were dissolved into three different solutions each of them with a fix pH (4.2; 6; 7.4). Then, CIP solutions were incubated at 37ºC to carry out the adsorption and desorption studies. The results were confirmed by Zeta potential (Z) and Fourier transformed infrared spectroscopy (FT-IR). Both, CIP and nanoparticles have a pH dependent behavior. Therefore, the variation of Z of nanoparticles adsorbed without CIP has varied from -19 to -14 mV meanwhile the pH of the solutions was increased. When the CIP was adsorbed onto nanoparticles, the Z range was from -15 to a -3.5 mV as the pH of the solutions was increased. These facts are consistent, on one hand, with surface features of nanoparticles which were previously reported; and on the other hand, with the ionization characteristics of the groups of CIP. Therefore, the typical FT-IR bands are displayed into samples with CIP, which demonstrate its presence on the surface of the nanoparticles. The release study shown that the maximum amount desorbed of CIP from nanoparticles was 1μg per mg of nanoparticles at pH 6, and the lower release of CIP was at higher pH with 0.1 μg per mg of nanoparticles. Finally, from this study it is shown that adsorption-desorption behavior of CIP from these nanoparticles is dependent of temperature, pH solution, and its concentration in the sample and therefore, this kind of systems could be a useful tool to address bone disease, such as osteomyelitis, in the future.