Trace Analysis of Lead and Copper Ions in Fish Tissue Using Paste Electrodes

Abstract

DNA was immobilized onto a carbon nanotube surface through cyclic voltammetry, in which paste electrode (PE) was subjected to lead and copper trace ion analysis. Optimized conditions for square‐wave stripping voltammetry were then searched. The results indicated three other linear working ranges—3–21 mg l⁻¹, 2–16 µg l⁻¹, and 3–17 ng l⁻¹ Pb(II) Cu(II)—within an accumulation time of 190 s in 0.1‐M ammonium phosphate electrolyte solutions of pH 10.0. At the optimized conditions, the detection limit (S/N) was pegged at 0.4 ng l⁻¹ (1.93×10⁻¹² M Pb(II) and 6.29×10⁻¹² M Cu(II)). And the relative standard deviation at 10 mg l⁻¹ Pb(II) and Cu(II) was a 0.074 and 0.069% precision, in 15 measurements. The method can be applied to assays of fish tissue.

Keywords:

• Paste electrode
• Pb(II)
• Cu(II)
• square wave voltammetry
• fish tissue