Application of tartrazine for sensitive and selective kinetic determination of Cu(II) traces

An efficient, highly sensitive, fast and selective kinetic method for determination of traces of Cu(II) was developed and applied for its quantification in different real samples. The method was based on the catalytic effect of Cu(II) traces on the redox reaction of artificial azo-dye tartrazine (tri-sodium-5-hydroxy-1-(4-sulfophenyl)-4-[(4-sulfophenyl)azo]pyrazole-3-carboxylate) with H2O2. The optimum operating conditions regarding reagent concentration were examined and established. Linearity of the method was obtained in the concentration range from 13 to 318 ng/mL of Cu(II), with a detection limit (LOD) (3s b/m) of 2 ng/mL, and limit of quantification (LOQ) (10s b/m) of 7 ng/mL. Obtained results for Cu(II) determination in analyzed samples, as well as the development and validation of the proposed analytical procedure are given and discussed.