Background: This study describes a simple and rapid analytical method for the simultaneous determination of trace amounts of copper(II), zinc(II), nickel(II), cobalt(II), iron(II), cadmium(II) and mercury(II) in fish samples by the reversed-phase highperformance liquid chromatography (RP-HPLC) with di-2-pyridyl ketone benzoylhydrazone (DPKBH) as pre-column derivatization reagent.
Methods: Seven metal chelates were successfully separated with methanol: acetonitrile: tetrabutyl ammonium bromide (1.0 mM): water mixture containing ammonium acetate buffer (pH 6.0) and DPKBH (1.0 mM) (40:24:1:30:5, v/v/v/v/v) as mobile phase on a C-18 column at a flow rate 1.0 mL min(-1) at 370 nm.
Results: Under the optimum conditions, reproducibilities of analyte retention times (relative standard deviation (RSD) <= 0.04%) and peak areas (RSD <= 1.5%) were found to be good with the lineraties R2 >= 0.9995. The validation of the method was performed by the analysis of certified reference materials.
Conclusion: The method developed was applied for the determination of Cu(II), Zn(II), Ni(II), Co(II), Fe(II), Cd(II) and Hg(II) in fish samples.