SPECTROPHOTOMETRIC DETERMINATION OF COPPER(II) IN PHARMACEUTICAL, BIOLOGICAL AND WATER SAMPLES BY 4-(2′-BENZOTHIAZOLYLAZO)-SALICYLIC ACID
A highly sensitive method is proposed to determine copper (II) ions by forming a stable complex through their interaction with 4-(2′-benzothiazolylazo)-salicylic acid (BTAS) at room temperature and pH of about 5.0. The complex gave a maximum absorption at 485 nm with a molar absorptivity coefficient of 2.35 · 104 l/(mol · cm). The linear range for the copper determination is 0.63-5.04 mg/l. The method could be applied to determine the copper ions in different biological specimens like some drugs and water samples.