Determination of trace copper in seawater by minicolumn field sampling technique

Cu in seawater samples were collected and pre-concentrated in site by on-line minicolumn field sampling(MFS) technique under the acidity of seawater,the adsorption materials of the column used for the first was Amberlite XAD-2 functionalized with dithizone(H_2D_Z)copolymer resin(XAD-H_2D_Z).Then in the laboratory,these minicolumns were determined by flow injectionflame atomic absorption spectrometry(FI-FAAS).The enrichment factor of 432 was obtained for 50 mL of sampling volumes,and the detection limit was 0.019 μg/L and relative standard deviation(5 μg/L,n=11) was 1.68% at the same conditions.The method was successfully applied to the determination of copper in a certified reference materials(GBW(E)080040) and in seawater samples from Dalian Laohutan,respectively,and the results was satisfactory.