Spectrophotometric Determination of Copper Complex by Bismarck Brown Y in Environmental and Pharmaceutical Samples

A simple and Sensitive method for the determination of trace amounts of copper by spectrophotometry is described, which is based on the formation of the copper- bismarck brown Y orange colored complex, in acetate buffer medium (pH = 4), which increases the sensitivity and the complex was extracted by chloroform. Under optimum conditions, the maximum absorption of the chloroform extract was measured at 420 nm. The Beer law was obeyed in the range of 0.40 to 5.2 ?g ml -1 of copper. The molar absorptivity and the Sandell's sensitivity of the complex were 1.8 x104 l mol -1 cm -1 and 0.2563 ?g cm-2, respectively. The detection limit was found to be 0.0120 ?g ml-1. A detailed study of various interfering ions made the method more sensitive. The method was successfully applied for the determination of Cu (II) in water and pharmaceutical samples. The performance of the present method was evaluated in terms of Student 't' test and Variance ratio 'f ' test, which indicate the significance of the present method over reported methods. It also provides a relative inexpensive alternative to more expensive instrumental method like AAS.