Fluorescência molecular em nanopartículas de sílica marcadas com quercetina e rodamina B

Abstract

Silica nanospheres doped with quercetin-Al +3 and rhodamine B were synthesized with high size control and morphology, using acid and basic catalysis of tetraethylorthosilicate (TEOS). The nanoparticle diameter obtained was about 200-300 nm, with higher regularity when synthesized in alkaline media. The Stöber's and core-shell methods were used as preparation methods. Because the alkaline hydrolysis of quercetin, the flavonoid or the quercetin-Al +3 complex doped nanoparticles showed higher emission intensity when acid catalysis was used. When basic catalysis was performed, the particles prepared with an alumina-sol showed expressive emission intensity, but nanometric parallelepipeds were obtained. The quercetin-alumina fluorescence decays are biexponential, agreeing with the two types of quercetin-Al +3 complexes formed in the nanoparticles domain. In the case of rhodamine B, fluorescence correlation spectroscopy (FCS) measurements were performed, showing a relation between diffusion relaxation with size and aggregation behavior.

Síntese, caracterização e estudo in vitro do potencial de mineralização do composto Quercetina-Sr>sup<2+>/sup<

“…É possível verificar que a banda referente ao anel B sofreu deslocamento batocrômico, ocorrendo por volta de 409 nm. Tal evidência, como no grupo 3OH com a carbonila do anel C 94,95 .…”