Original Articles
K. Vasudeva Reddy, D. Nagarjun
Abstract
2-Acetylpyridine-4-methyl-3-thiosemicarbazone (APMT) is proposed as a new sensitive reagent for spectrophotometric determination of zinc (II). APMT reacts with zinc (II) in the pH range 5.5 - 6.5 to form yellow coloured complex. The absorbance value of Zn (II) - APMT complex was measured at different intervals of time at 365 nm, to ascertain the stability of the complex. It was observed that the colour development was instantaneous and stable for more than 48 h. The system obeyed Beer's law upto 1.05 μg mL-1 of zinc(II). The molar absorptive and Sandell's sensitivity of the species is 3.5 X 104 L mol-1 cm-1 and 1.9 X 10-3 μg cm-2 at 365 nm. The composition of the zinc (II) complex with APMT was studied by Job's continuous variation and molar ratio method. Various certified reference materials (NIST 1573 and NBS 1572) have been tested for the determination of zinc for evaluating the accuracy of the developed method. The results of the proposed method are in agreement with AAS method.