A new method for simultaneous determination of Co(II), Ni(II) and Pd(II) as morpholine-4-carbodithioate complex by SPME-HPLC-UV system

A new approach for the analysis of Co(II), Ni(II) and Pd(II) as morpholine-4-carbodithioate (MDTC) complexes in aqueous medium by using solid phase microextraction (SPME)-high performance liquid chromatography (HPLC)-UV has been developed. The method involves sorption of metal complexes on PDMS fiber from aqueous solution followed by desorption in the desorption chamber of SPME-HPLC interface using acetonitrile:water (60:40) as mobile phase. A good separation of metal complexes is achieved on C₁₈ column. The detection limits of Co(II), Ni(II) and Pd(II) are 0.17, 0.11 and 0.06 ng ml⁻¹, respectively. These can be determined by the proposed method without interference from other common metal ions such as Mo(VI), V(V), Ag(I), Sn(IV), Cd(II), Pb(II), Zn(II), Ag(I), Sn(II), Cr(III) and Cr(VI). The method was applied to the determination of these metals in different alloy samples and drinking water sample.