Determination of Trace Copper with a Novel Kinetic Procedure/O_2-gallocyanine Indicator Reaction

摘要

A novel kinetic procedure for determination of trace copper was proposed based on the catalytic effect of Cu~2+ on the aerial oxidation of gallocyanine (GC), by which GC was oxidized and a colorless product was produced. The reaction was monitored spectrophotometriclaly in hexamethylene tetramine-hydorcohloric acid buffer solution. The calibration graph is linear for 0.05～0.5 μ g/ml, and the detection limit is 0.02 μg/ml (Cu~2+). The selectivity for copper is satisfied as the interference's of Fe~3+ and Al~3+ could be easily and effectively eliminated by the addition of NH_4HF_2. The method was applied to the determination of copper in soil, tap water and simulated water samples, and the results were satisfactory.