Antioxidative and antiinflammatory activities of quercetin-loaded silica nanoparticles

Utilizing the biological activities of compounds by encapsulating natural components in stable nanoparticlesis an important strategy for a variety of biomedical and healthcare applications. In this study, quercetin-loaded silica nanoparticleswere synthesized using an oil-in-water microemulsion method, which is a suitable system for producing functional nanoparticlesof controlled size and shape. The resulting quercetin-loaded silica nanoparticleswere spherical, highly monodispersed, and stable in an aqueous system. Superoxide radical scavenging effects were found for the quercetin-loaded silica nanoparticlesas well as free quercetin. The quercetin-loaded silica nanoparticlesshowed cell viability comparable to that of the controls. The amounts of proinflammatory cytokines produced by macrophages, such as interleukin 1 beta, interleukin 6, and tumor necrosis factor alpha, were reduced significantly for the quercetin-loaded silica nanoparticles. These results suggest that the antioxidative and antiinflammatory activities of quercetinare maintained after encapsulation in silica. Silica nanoparticlescan be used for the effective and stable incorporation of biologically active natural components into composite biomaterials.