Speciation of the ternary complexes formed between copper(II), salicylic acid and small blood serum bioligands.

In this work we present the speciation of the ternary complexes formed between the copper(II)-salicylate (Sal 2 − ) system and the small blood serum bioligands, such as lactate (Lac − ), oxalate (Ox 2 − ), citrate (Cit 3 − ) and phosphate (PO 4 3 − ). The speciation of the ternary systems were studied by pH-potentiometry at 25 °C and using an ionic strength I = 1.0 mol·dm − 3 KNO 3 . In the Cu(II)-Sal 2 − − Lac − system the complexes [Cu(Sal)(Lac)(OH)] 2 − , [Cu(Sal)(Lac)(OH) 2 ] 3 − and [Cu(Sal) 2 (Lac)] 3 − were detected. In the case of the Cu(II)-Sal 2 − –Ox 2 − system the complexes [Cu(Sal)(Ox)] 2 − , [Cu(Sal)(Ox)(OH)] 3 − and [Cu(Sal)(Ox)(OH) 2 ] 4 − were observed. In the Cu(II)-Sal 2 − − Cit 3 − system the species [Cu(Sal)(H 2 Cit)] − , [Cu(Sal)(HCit)] 2 − , [Cu(Sal)(Cit)] 3 − and [Cu(Sal)(Cit)(OH)] 4 − were detected and in the Cu(II)-Sal 2 − –PO 4 3 − system the complexes [Cu(Sal)(H 2 PO 4 )] − , [Cu(Sal)(HPO 4 )] 2 − and [Cu(Sal)(PO 4 )] 3 − were observed. [ABSTRACT FROM AUTHOR]