A new, simple, sensitive and rapid spectrophotometric method is proposed for the determination of trace amount of nickel(II). The method is based on the formation of a 1:2 complex with 1-(4'- pyrazolon azo) 2,7-naphthalendiol (1-APANDOL) as a new reagent is developed . The complex has a maximum absorption at 514 nm and εmax of 2.0x104 L mol-1 cm-1. A linear correlation (0.1-2.0 μg mL-1) was found between absorbance at λmax and concentration. The accuracy and reproducibility of the determination method for various known amounts of nickel(II) were tested. The results obtained are both precise (RSD was better than 0.63%) and accurate (relative error was better than 0.2%). The effect of diverse ions on the determination of nickel(II) to investigate the selectivity of the method were also studied. The stability constant of the product was 0.13x108L mol-1. The proposed method was successfully applied to the analysis of synthetic mixtures and tea sample without any preliminary concentration or separation.
Nickel(II) determination, Spectrophotometry, Antipyriyl azo 2,7-naphthalendiol, Tea leaves