Electrophoretic studies of biologically important mixed metal - Ascorbic acid -Nitrilotriacetate complexes

Quantitative indication of a complex formation comes from the estimation of the stability or formation constants characterizing the equilibria corresponding to the successive addition of ligands. The binary equilibria of metal (II) / (III)-ascorbic acid and also mixed equilibria metal (II) / (III)-ascorbic acid-NTA have been studied using ionophoretic technique. The stability constants of metal-ascorbic acid binary complexes are found to be 10 ^3.77, 10 ^2.47,10 ^2.27 and that of metal-ascorbic acid-NTA mixed complexes have been found to be 10 ^6.05, 10 ^5.93, 10 ^5.75, for Fe(III), Cu(II) and Co(II) complexes, respectively at 25 °C and ionic strength I _c = 0.1 mol dm ^-3 (HClO ₄).