Spectrophotometric Investigation of Uranil(II)−Rutin Complex in 70 Ethanol

The composition and stability constant of a UO 2 (II)-rutin complex in 70% ethanol were determined by suitable spectrophotometric methods and pH measurement. UO 2 (II) ion and rutin (3,3‘,4‘,5,7-pentahydroxyflavone-3-rhamnoglucoside) form a 1:1 complex in which the UO 2 (II) ion is linked to rutin through the carbonyl and 5-hydroxyl group. The concentration stability constant of the complex, log β 1, ranged from 6.57 at pH 4.00 to 4.72 at pH 7.00. Conditions for spectrophotometric determination of rutin, by complex formation with UO 2 (II) ion, were investigated. Beer's law was obeyed in the concentration range from 1.0 × 10 - 5 to 2.0 × 10 - 4 M for rutin. Determination of rutin in Rutinion forte tablets was demonstrated.