Spectrophotometric method for the determination of ziram and zineb with 1-(2-thiazolylazo)-2-naphthol (TAN) using Triton X-100 as the solubilizing agent

Department of Chemistry, Punjabi University, Patiala-147 002, India

E-mail : aljrao@rediffmail.com

Manuscript received 12 November 2002, revised 23 April 2003, accepted 6 May 2003

A new, rapid, sensitive and selective method has been developed for the determination of ziram and zineb using 1-(2- thiazolylazo)-2-naphthol (TAN) as the complexing reagent in the pH range of 8.0-8.5 in the presence of octylphenolpoly(ethylene glycol) ether i.e. Triton X-100. The violet complex shows λ_max, at 580 nm. The molar absorptivity is 7.52 x 10⁴ dm³ mol^-1 cm^-1 for ziram and zineb and Sandell's sensitivity 0.0040 and 0.0036 µg cm^-2 for ziram and zineb, respectively. The method has been used for direct determination of ziram and zineb in synthetic mixtures, commercial for­mulations and crops residue.