Engineering a bromophenol derivative for rapid detection of Hg2+/CH3Hg+ in both environmental and biological samples through a unique activation process

Abstract

Reaction-based sensory systems are always preferred for detecting Hg²⁺ and its organic form, CH₃Hg⁺. A simple bromophenol derivative (BDT) has been developed as a cheap, small and ultrasensitive sensor for both Hg²⁺ and CH₃Hg⁺ ions with rapid detection ability. The transformation of the 1,3-dithiolane segment to the formyl group has been utilized here as a key feature for the turn “off–on” fluorescence response due to the activation of the ESIPT process during the detection of the analytes. Most of the 1,3-dithiolane systems required a long response time for CH₃Hg⁺, but BDT has been demonstrated as an excellent system that required a low response time to detect the organic form of mercury. Having a limit of detection (LOD) value of 3.8 nM and 0.8 μM towards Hg²⁺ and CH₃Hg⁺ respectively in an aqueous medium, BDT served as an excellent detection probe with environmental detection capability. It has been supported by ICP-MS analysis of commercially available vermilion. BDT has been utilized to detect Hg²⁺ in a biological system with excellent efficiency along with ecological and real sample analysis. Furthermore, the desulfurization process triggered by Hg²⁺ has been proved using ¹H NMR analysis and spectroscopic fluorescence techniques. These observations encouraged us to claim BDT as an excellent cheap and easily synthesizable efficient tool for detecting inorganic and organic mercury in controlled, environmental, and biological systems.