Spectrophotometric Determination of Zinc in Pharmaceutical and Biological Samples with Di‐2‐pyridyl Ketone Benzoylhydrazone: a Simple, Fast, Accurate and Sensitive Method

Abstract

A simple, fast, accurate, and sensitive spectrophotometric method was developed to determine zinc(II). This method is based on the reaction of Zn(II) with di‐2‐pyridyl ketone benzoylhydrazone (DPKBH), at pH=5.5 and 50% (v/v) ethanol. Beeŕs law was obeyed in the range 0.020–1.82 µg mL⁻¹ with a molar apsorptivity of 3.64×10⁴ L mol⁻¹ cm⁻¹, and a detection limit (3δ) of 2.29 µg L⁻¹. The action of some interfering ions was verified and the developed method applied to pharmaceutical and biological samples. The results were then compared with those obtained by using a flame atomic absorption technique.

Keywords:

• Zinc
• DPKBH
• hydrazones
• pharmaceutical samples
• biological samples
• spectrophotometry

The authors are grateful to FAPEMIG, FINEP, and CNPq for the financial support.