Interaction of silica and betamethasone loaded silica nanoparticles with monocytes

MEBERT ANDREA MATHILDE; ALVAREZ GISELA SOLANGE; DE MARZI MAURICIO; DÍAZ LUIS EDUARDO; MALCHIODI EMILIO; DESIMONE MARTIN FEDERICO

Potrero de los Funes, San Luis

Congreso; 47th Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2011

Abstract: Silica nanoparticles (SiNP) were investigated for their potential use as a novel drug carrier for targeted and controlled release of drugs. Betamethasone is a potent glucocorticoid steroid with anti-inflammatory and immunosuppressive properties. In this work, betamethasone was encapsulated into monodisperse dense amorphous silica nanoparticles, to be used as a drug delivery system for the treatment of inflammatory and autoimmune diseases. SiNP were prepared via base-catalyzed hydrolysis and polymerization of tetraethyl orthosilicate under sterile conditions using ammonia (Stöber process), dialyzed and characterized before use. SiNP sizes were determined by dynamic light scattering (310 nm). In vitro studies were conducted on monocyte cells cultures for 24 and 48 h with culture media, free drug (20 µg/ml), betamethasone loaded SiNP (1 µg/ml) or SiNP without drug as controls. SiNP did not induce any morphological change in monocytes after exposure. Cell proliferation (evaluated with the MTT test of tetrazolium reduction) is not affected in the presence of free betamethasone, while SiNP significantly stimulate monocytes proliferation. This stimulation was effectively inhibited by betamethasone loaded SiNP. These results suggest that SiNP could be use as drug carrier, although several factors such as size and charge of the SiNP must be further analyzed.