Determination of nickel in biological samples by inductively coupled plasma atomic emission spectrometry after extraction with 1,5-bis[phenyl-(2-pyridyl)methylene]thiocarbonohydrazide

Abstract

A sensitive inductively coupled plasma atomic emission spectrometric method for the determination of trace amounts of nickel after extraction of the metal into isobutyl methyl ketone (IBMK) containing 1,5-bis[phenyl(2-pyridyl)methylene]thiocarbonohydrazide (BPTH) is described. A systematic study was made to determine the optimum conditions for extraction of the metal into IBMK. The chief advantage of the method lies in the maximum allowable aqueous-to-organic phase volume ratio of 37. The detection and quantification limits for nickel were 0.3 and 1.1 ng ml^–1, respectively, and the calibration is linear from 0.4 to at least 150 ng ml^–1. The method has been used for the determination of nickel in various biological samples [mineralized by microwave digestion in sealed poly(tetrafluoroethylene) containers], as well as in human urine, with good results.