The nickel(II), palladium (11) and oxovanadium (IV) chelates of bis(acetylpivalyl-methane)meso-stilbenediimine(meso-H2APM2S), copper(II), nickel(II), palladium(II) and oxovanadium(IV) chelates of bis(acetylpivalylmethane)dl-stilbenediimine (dl-H2APM2S), bis-(isovalerylacetone)meso-stilbenediimine (meso-H2IV2S) and bis(isovaleroylacetone)dl-stilbene-diimine (dl-H2IVA2S) have been separated on reversed phase HPLC columns (250 x 4 mm) packed with Hypersil ODS 5mu and (150 x 3.9 mm) Nova Pak C-18 with guard ODS column. The copper, nickel, palladium and oxovanadium chelates of dl-H2IVA2S are also separated on normal phase HPLC column (250 x 4 mm) packed with licrosorb Si, 100 5mu. The detection is achieved using variable wavelength UV detector. The linear calibration range is observed at ng levels and detection limits at sub ng levels of metal chelates. Finally the effect of methyl and phenyl group substitution on the relative elution of copper, nickel and palladium chelates on Nova Pak C-18 column has been examined and evaluated.


M Y KHUHAWAR ,ALTAF I SOOMRO ,