Evaluation of 2,6-diacetylpyridinebis-4-phenyl-3-thiosemicarbazone as complexing reagent for zinc in food and environmental samples

Abstract

An evaluation of analytical reagent, 2,6-diacetylpyridine-bis-4-phenyl-3-thiosemicarbazone (2,6-DAPBPTSC) for traces of Zn(II) in foods and environmental samples by the development of a simple, sensitive and selective extractive spectrophotometric method was undertaken. It gave a 1:1(M:L) Zn(II)–2,6-DAPBPTSC yellowish orange colored complex at pH 4.5, was easily extractable into n-butanol and has shown maximum absorbance at 490 nm. It obeys Beer’s law in the range of 1.06–13.6 μg mL−1 of Zn(II). The molar absorptivity, Sandell’s sensitivity and detection limit were found to be 0.471 × 104 L mol−1 cm−1, 0.0138 μg cm−2 and 0.0081 μg mL−1, respectively. The correlation co-efficient of the complex (r = 0.985) indicates good linearity between two variables such as absorbance of complex and amount of zinc. The proposed procedure was applied to traces of Zn(II) in foods and environmental samples. Results were compared with those obtained using an AAS and statical validation of the method was tested in terms of Student ‘T’ test and variance ‘F’ test, which indicate the significance of the present method.

Keywords

• Foods
• Environmental samples
• Zn(II)
• 2,6-Diacetylpyridinebis-4-phenyl-3-thiosemicarbazone
• Extractive spectrophotometric method