Hg²⁺-selective fluorescent probe based on rhodamine 6G and its application in aqueous media

Abstract

Based on rhodamine 6G, a highly sensitive and selective fluorescent sensor R6G1 for Hg²⁺ detection had been designed and prepared. It was synthesized through the well-known reaction that thiourea derivatives with amine could easily be transformed into guanidine derivatives with the promotion of Hg²⁺. By coordination with Hg²⁺, R6G1 exhibited high sensitivity and selectivity over other metal ions in aqueous systems. Furthermore, fluorescence titration experiments established the well-fitted linearity function of the fluorescent intensity with the concentration of Hg²⁺ in aqueous solution. The results showed that R6G1 provided high water solubility and high selectivity toward Hg²⁺ but no significant response toward other competitive cations and anions. It was suggested that the chemosensor would find its application in environmental field requiring rapid and accurate Hg²⁺ ion analysis.

Keywords:

• Rhodamine
• Fluorescent probe
• Hg²⁺
• Synthesis
• Spectral properties

Acknowledgement

The work was supported by the key project in Yunnan Provincial Education Department (2014Z092), YMU-DEAKIN International Associated Laboratory on Functional Materials, Key Laboratory of Resource Clean Conversion in Ethnic Region, Education Department of Yunnan Province (117-02001001002107), and Joint Research Centre for International Cross-border Ethnic Regions Biomass Clean Utilization in Yunnan.

Notes

Presented at the 8th International Conference on Challenges in Environmental Science & Engineering (CESE-2015) 28 September–2 October 2015, Sydney, Australia