A Novel Method for the Spectrophotometric Determination of Thallium Using Methiomeprazine Hydrochloride

摘要

A new,simple,sensitive,and rapid Spectrophotometric method is proposed for the determination of trace amounts of thallium(III).The method is based on the oxidation of methiomeprazine hydrochloride by thallium(III) in phosphoric acid medium to give a blue radical cation,having a maximum absorption at 645 nm.Beer's law is valid over the concentration range 0.5-4.0 mug mL~(-1),with molar absorptivity and Sandell's sensitivity of 3.2 x 10~4 L mol~(-1) cm~(-1) and 0.0064 mug cm~(-2),respectively.The detection limit of thallium determination is 0.01 mug mL~(-1).The tolerance limits for interfering ions are discussed.All variables were studied in order to optimize the reaction conditions.The efficacy of the proposed method is shown by the successful determination of traces of thallium in alloys,minerals,standard reference materials,water,and urine samples.