Preconcentration of Lead Using Mercaptosephadex and Its Determination with New Reagent by Spectrophotometry

A highly sensitive and selective spectrophotometric method for the determination of traces of Lead in water after pre-concentration using Mercapto sephadex (MS-50) has been developed. The method is based on the color reaction of lead (II) with dichlorohydroxyl phenyl porphyrin. Under the optimum condition, Pb(II) reacts with reagent to from 1:2 yellow complex in presence of Triton X-100, which has a maximum absorption peak at 482 nm. The color reaction can be completed rapidly and remain stable for more than 24 h at room temperature. The molar absorption co-efficient of the lead complex, the limit of quantification, the limit of detection and relative standard deviations were found to be 2.45 H 10 L Mol cm-1, 4.4, 1.45 ng ml and 1% respectively. The absorbance of the lead complex at 482 nm is linear up to 0.46 μg ml-1 of lead(II). The effect of various co-existing ions in water were examined seriously. No interfere was observed. Moreover, a simple pre -concentration method for trace of lead in water was also studied using MS-50. It was found that traces in lead in water can be absorbed.