The determination of trace elements as cobalt, copper, nickel and iron in different biologycal and environmental samples with high performance liquid chromatograpy

The trans metal ions such as Fe(III), Ni(II) and Co(III) were materialized by highperformance liquid chromatography (HPLC) analyses in various plants by preparingcomplexes with 4-(2- pyridiylazo) resorcinol (PAR) ligand.The suitable conditions to prepare complex with PAR ligand of Fe(III), Ni(II),Co(III) and Cu(II) ions are investigated. The stoichiometries of complexes that formed ionsabove mentioned with PAR were determined that [Metal]/[Ligand] is 1:2 for Fe(III), Ni(II),Co(III) and is 1:1 for Cu ions by using mol rates and job method. Complex formationperiods for Fe(III), Ni(II), Co(III) and Cu(II) complexes were found as 10-60 seconds inpresence of methanol-water.The wavelengths of maximum absorbance for Fe(III), Ni(II), Co(III) and Cu(II)complexes were determined as 490 nm, 504 nm, 510 nm and 500 nm, respectively. Themost suitable pH values of complex formation for Co-PAR, Fe-PAR, Ni-PAR and Cu-PARwere determined in 5-8, 4-6.5, 6-10 and 6-9 range, respectively.The molar absorption coefficients of complexes for Fe-PAR, Ni-PAR, Co-PAR andCu-PAR were found as 5,4x104, 2,7x104 6,5x104, , 4,2x104 mol L-1 cm-1, respectively. ThepH of mobil phase was determined as 5,3 under chromatographycal separation conditionsoptimized in column C18 5µ 100A Luna (250x4,6 mm) ODS by using UV-Visible detector:wave length 500 nm, flow rate 0,6 mL/min, mobile phase composition;methanol/water/acetonitrile/acetate solutionDetection limits of process for Fe-PAR, Ni-PAR and Co-PAR under optimizedconditions were found as 4.45, 3.26 and 1.86 µg.L-1, respectively. The analysis of Fe, Ni andCo ions in plant samples under optimized conditions were carried out by HPLC.Key Words: HPLC, Trace Element, 4-(2-pyridylazo)-resorcinol, UV-Visible, Iron, Nickel,Cobalt, PAR, Resorcinol.