Determination of nickel in tea with arsenazo-III by spectrophotometry

Ai-Fang Geng and Qing-Zhou Zha

Abstract

Using arsenazo-III as chromogenic reagent, a spectrophotometric method for the determination of nickel was developed. The maximum absorption wavelength of nickel complex is 610 nm. Beer's law is conformed over the range of 0.2 ~ 4.0 μ g / mL for nickel. The apparent molar absorption coefficient of method is ε540 nm = 1.76 × 104 L·mol-1·cm-1 and detection limit is 0.093 μ g / mL. The present method has been already applied to the determination of nickel in tea and method recovery is between 99.7% ～ 100.1%.