Single-channel flow injection spectrophotometric determination of nickel using furildioxime in micellar solution.

A very simple, selective, and fast flow injection spectrophotometeric method is developed for determination of nickel using furildioxime as complexing agent. Micellar solution of brij-35 is employed to solubilize the sparingly soluble complex of Ni-furildioxime in buffered aqueous system (pH-9.00). Under optimized conditions, absorbance is linear from 0.02 to 10 μg mL(-1) using 500 μL sample volume and from 10 to 30 μg mL(-1) using 50 μL sample volume of nickel at 480 nm, with R(2) = 0.9971 and 0.9916, respectively. The molar absorption coefficient and Sandell's sensitivity were 6.0 × 10(3) L mol(-1) cm(-1) and 0.01 ng cm(-2), respectively. The sample throughput of the method is 120 samples per hour with RSD of 0.01-0.2% for 0.02 to 10 μg mL(-1) nickel (n = 5), indicating that the method is highly precise and reproducible. Interference from cobalt is removed by Nitroso R-salt-modified XAD-16. The developed method is validated by analysing certified reference materials and is applied to assess nickel content of commercially available cigarettes.