Complexation of luteolin with lead (II): Spectroscopy characterization and theoretical researches.

The interactions of (CH3COO)2Pb·3H2O (lead acetate trihydrate) with luteolin, 5,7,3',4'-tetrahydroxyflavone, were investigated in methanol solution. The spectroscopy (UV-Vis, FT-IR, HPLC-MS, 1H NMR) and elemental analysis were adopted to assess the interaction of luteolin and Pb(II). The results show that luteolin reacts with Pb(II) through the chelating sites of 4‑carbonyl and 5-hydroxy in two luteolin molecules. The structures, energies, CDA (charge decomposition analysis) and orbitals analysis of the ligand and complex have been analyzed according to quantum-chemical calculation, which is further proofed that luteolin molecule can effectively chelate Pb(II) by 5-hydroxyl-4-oxo chelating site. It is speculated that luteolin has a high potential of becoming a health care product to eliminate lead cation in the future.