Quercetin immobilized on silica gel as a solid phase reagent for tin(IV) determination by using the sorption-spectroscopic method.

New chelating sorbents are prepared by 3,3',4',5,7-pentahydroxyflavone adsorption from butanol and acetone-hexane (1:4) solutions, characterized by isotherm of sorption, IR-spectroscopy and studied for pre-concentrating and sorption-spectroscopic determination of Sn(IV). The solid-phase Quercetin with satisfactory analytical characteristics was formed by adsorption from acetone-hexane (1:4) mixture. The quantitative recovery of Sn(IV) from aqueous solution with modified sorbent was observed at pH 1.8-2.2. The tolerance limits of heavy metal ions in the sorption of Sn(IV) are reported. The limit of Sn detection is 0.06 mg l(-1). The linearity of calibration graph has been observed up to 1.2 mg l(-1). The method has been applied to determine Sn in high purity zinc materials.