ADSORPTION ISOTHERMS AND KINETICS OF BIOACTIVE FLAVONOID QUERCETIN ONTO AMINO-FUNCTIONALIZED SILICA NANOADSORBENT

Flavonoids are the most abundant polyphenolic compounds found in plants, particularly in the leaves, fruits, nuts, skins, flowers, and plant extracts such as tea. There have been numerous investigations of flavonoids in recent years because of their beneficial pharmacological properties, such as antioxidant, antitumor, antibacterial, and anti-mutagenic activity and cardiovascular protection. In the present study, kinetics and thermodynamics of adsorption flavonoid quercetin on nanosilica particles was followed by UV-Vis spectroscopy at temperature 250C. Adsorption isotherms were derived on the basis of batch analysis. Isotherm data were treated according to Langmuir and Freundlich models. In addition, the obtained data were treated according to pseudo-firstorder, pseudo-second-order kinetic models. The effect of environment pH and the effect of solvent on adsorption process were also evaluated. The results obtained show that amino-functionalized nanosilica particles are found to exhibit significantly increased adsorption capacities compared to non-functionalized materials.