A chemosensor for heavy-transition metal ions in mixed aqueous-organic media

Abstract

A new chemosensor (L₁) is synthesized and its spectral response was screened with most alkali, alkaline earth, transition and lanthanide metal ions in THF-water (2:3, v/v, pH 7.2, 20 mM HEPES buffer) medium. This is found to bind four different transition metal ions such as Hg²⁺, Cu²⁺, Ag⁺ and Ni²⁺ in mixed aqueous solution at pH 7.2; while binding affinity towards the Hg²⁺ is found to be an order of magnitude higher as compared to other three cations mentioned. Experimental results reveal that the L₁ could be used for colorimetric detection of Hg²⁺, present in the lower organism like Pseudomonas putida.