Chaisuksant R, Palkawong-Na-Ayuthaya W, Grudpan K
Department of Chemistry, Faculty of Science, Silpakorn University, Nakorn Pathom 73000, Thailand.
Talanta. 2000 Dec 4;53(3):579-85. doi: 10.1016/s0039-9140(00)00534-8.
Naphthazarin (5,8-dihydroxy-1,4-naphthoquinone; Naph) is proposed as a chromogenic reagent for the spectrophotometric determination of copper(II). The polynuclear complex has a mole ratio of Cu:Naph=4:6 in a 50% v/v ethanol/water medium containing 0.1 M ammonium acetate and 1.5% (w/v) sodium dodecyl sulfate. The copper-naphthazarin complex shows an absorption maximum at 330 nm with a molar absorptivity of 1.84x10(4) l mol(-1) cm(-1). Beer's law is obeyed up to 4.5 ppm of copper(II). The method was applied for copper determination in alloy samples with satisfactory results.
