Analytical applications of microemulsions. Spectrophotometric determination of zinc using dithizone

Abstract

The use of sodium dodecyl sulphate oil-in-water microemulsions as a single-phase medium for ‘solvent extraction’ is considered, with particular reference to the determination of zinc by complexation with dithizone. The solubilities of dithizone and the zinc-dithizone complex in aqueous, micellar and microemulsion media were determined and aqueous zinc standards covering the range 0–10 mg l^–1 were analysed by batch and flow injection procedures. The effects of surfactant, cosurfactant and oil concentrations on the sensitivity of the method are discussed.