title: Development of highly sensitive extractive spectrophotometric determination of nickel(II) in medicinal leaves, soil, industrial effluents and standard alloy samples using pyridoxal-4-phenyl-3-thiosemicarbazone.
abstract: Pyridoxal-4-phenyl-3-thiosemicarbazone (PPT) is proposed as a new sensitive reagent for the extractive spectrophotometric determination of nickel(II). PPT reacts with nickel(II) in the pH range 4.0-6.0 to form a reddish brown colored complex, which was well-extracted into n-butanol. The absorbance value of the Ni(II)-PPT complex was measured at different time intervals at 430nm, to ascertain the stability of the complex. The system obeyed Beer's law up to 0.5-5.0microgmL(-1) of nickel(II), with an excellent linearity in terms of the correlation coefficient value of 0.99. The molar absorptivity and Sandell's sensitivity of the extracted species are 1.92 x 10(4)Lmol(-1)cm(-1) and 0.003057microgcm(-2) respectively at 430nm. The detection limit of the method is 0.069microgmL(-1). To assess precision and accuracy of the developed method, determinations were carried out at different concentrations. The relative standard deviation of all measurements does not exceed 2.62%. The developed method has been satisfactorily applied for the determination of nickel(II), when present alone or in the presence of diverse ions, which are usually associated with nickel(II) in medicinal leaves, soil and industrial effluent samples. Various standard and certified reference materials (CM 247 LC, IN 718, BCS 233, 266, 253 and 251) have also been tested for the determination of nickel for the purpose of validation of the present method. The results of the proposed method are compared with those obtained from an atomic absorption spectrometer (AAS).
authors.affiliation: Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan.
authors.forename: Loka Subramanyam
authors.initials: LS
authors.lastname: Sarma
authors.forename: Jyothi Rajesh
authors.initials: JR
authors.lastname: Kumar
authors.forename: Koduru Janardhan
authors.initials: KJ
authors.lastname: Reddy
authors.forename: Thenepalli
authors.initials: T
authors.lastname: Thriveni
authors.forename: Ammireddy Varada
authors.initials: AV
authors.lastname: Reddy
mesh_terms: D000497:Alloys / Q000737:chemistry*; D009532:Nickel / Q000032:analysis*; D018515:Plant Leaves / Q000737:chemistry*; D010946:Plants, Medicinal / Q000737:chemistry*; D011730:Pyridoxal / Q000031:analogs & derivatives* / Q000737:chemistry; D012680:Sensitivity and Specificity; D012987:Soil / Q000032:analysis*; D013053:Spectrophotometry; D013882:Thiosemicarbazones / Q000737:chemistry*
chemical_list: D000497:Alloys; D012987:Soil; D013882:Thiosemicarbazones; C502875:pyridoxal-4-phenyl-3-thiosemicarbazone; D011730:Pyridoxal; D009532:Nickel