Synthesis of (8-hydroxyquinolin-5-yl) methyl-4-nitrobenzoate as a fluorescence sensor for Zn²⁺ detection.

 The purpose of this study is to synthesize and analyze the efficiency of (8-hydroxyquinolin-5-yl) methyl-4-nitrobenzoate (5HM-8HQ-NO₂)  as a fluorescent sensor for the detection of Zn²⁺ ions in a given medium. The alcohol, 5-hydroxymethyl-8-hydroxyquinoline (5HM-8HQ) was synthesized initially from 8-hydroxyquinoline which was then converted to 5HM-8HQ-NO₂ through Steglich esterification with p-nitro benzoic acid. The absorption and emission spectra of 5HM-8HQ-NO₂ dissolved in acetonitrile, were analyzed with varying concentrations of Zn²⁺ ions.   Through conducting ratiometric fluorescence analysis, it could be concluded that 5HM-8HQ-NO₂ has a high efficacy to be utilized as a ratiometric fluorescence sensor for Zn²⁺ detection.