The reagent anthrone phenylhydrazone (APH) is used for the simultaneous determination of Co(II), Ni(II) & Cu(II) by fourth order derivative spectrophotometric method. The reagent APH gives light yellow colour with Co(II), Ni(II) & Cu(II) solution in basic medium. The maximum peaks were observed between 426.3-625 nm for Co(II), Ni(II) & Cu(II) in basic buffer solution of pH 10. The molar absorptivity and Sandell`s sensitivity of Co(II), Ni(II) & Cu(II)-APH complexes are computed, the molar absorptivity are 1.5x10 4 L/mol/cm, 2.0x10 4 L/mol/cm and 2.163x10 4 L/mol/cm respectively. The Sandell`s sensitivity are 0.0066 µg/cm 2 , 0.005 µg/cm 2 and 0.0026 µg/cm 2 respectively. The stability constant of Co(II), Ni(II) & Cu(II)-APH complexes are 1.530x10 5 , 2.486x10 4 and 2.96x10 4 respectively. The effect of various concentrations of Co(II), Ni(II) & Cu(II) ions on amplitude also studied. The samples of grape leaves, sesame, laver, mung bean and alloy samples were analyzed by the proposed method. The results of the food samples and alloy samples are good agreement with the results of APARI, AAS methods.

A new reagent namely 3,4-Dihydroxybenzaldehyde Thiosemicarbazone (3, synthesized by the authors for the determination of uranium(VI) in monazite sand, pitchblend ore, spiked water, human hair and human blood samples. A brown colored complex was formed between uranium(VI) and 3,4-DHBTSC in a media of pH 7. The developed method can be conveniently applied for the analytical determination of uranium (VI) in the concentration range 0.476 -4.760 µg/ml. The molar absorptivity and sandell`s sensitivity were found to be 2.0833x10 4 L/mol/cm and 0.0114 µg/cm 2 respectively. The proposed method was found to be linear (R>0.01), selective, accurate (recovery=<99.7%) and precise (RSD<1.1%) in the reported linear calibration line.