Development of an extractive spectrophotometric method for the determination of copper(II) in leafy vegetable and pharmaceutical samples using pyridoxal-4-phenyl-3-thiosemicarbazone (PPT).
A highly sensitive extractive spectrophotometric method has been developed for the determination of copper(II) using pyridoxal-4-phenyl-3-thiosemicarbazone(PPT) as an analytical reagent. The PPT forms reddish brown species of copper(II) at a pH range of 3.0-5.5, and the complex was extracted into n-butanol. The Cu(II)-PPT complex shows maximum absorbance at 440 nm, with molar absorptivity and Sandell's sensitivity being 2.16 x 10(4) L mol(-1) cm(-1) and 2.94 x 10(-3) microg cm(-2), respectively. The system obeys Beer's law in the range of 0.2-5.0 mg/L. The regression coefficient of the Beer's law straight line is 0.338, and the correlation coefficient is 0.96. The detection limit of the method is 0.0065 microg mL(-1). Most of the common metal ions generally found associated with copper do not interfere. The repeatability of the method was checked by finding the relative standard deviation. The developed method has been successfully employed for the determination of copper(II) in leafy vegetable and pharmaceutical samples. The method is evaluated by analyzing samples from the Bureau of Analyzed Samples (BCS 233, 266, 216/1, 207, and 179) and by intercomparison of experimental values using AAS.
Analytical Chemistry Division, Department of Chemistry, Sri Venkateswara University, Tirupati 517 502, A.P., India.
L Subramanyam
LS
Sarma
J Rajesh
JR
Kumar
K Janardhan
KJ
Reddy
A Varada
AV
Reddy
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003300:Copper / Q000032:analysis* / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D004364:Pharmaceutical Preparations / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D011730:Pyridoxal / Q000031:analogs & derivatives*; D012680:Sensitivity and Specificity; D013053:Spectrophotometry / Q000379:methods*; D013882:Thiosemicarbazones; D014675:Vegetables / Q000737:chemistry*
D007202:Indicators and Reagents; D004364:Pharmaceutical Preparations; D013882:Thiosemicarbazones; C502875:pyridoxal-4-phenyl-3-thiosemicarbazone; D011730:Pyridoxal; D003300:Copper