Development of optical sensing probe for Hg(II) ions detection in ground water using Au, Hexanedithiol and Rhodamine B nanocomposite system

作者：Daware Krishna; Shinde Rakesh; Kalubarme Ramchandra S; Kasture Manasi; Pandey Ashok; Terashima Chiaki; Gosavi Suresh W^*

来源：Sensors and Actuators B: Chemical , 2018, 265: 547-555.

DOI：10.1016/j.snb.2018.03.095

• Hg(II) ion detection
• Functionalized AuNPs
• Absorbance
• Fluorescence
• Rhodamine B
• Hexanedithiol

Development of simple, sensitive and selective detection probe for Hg(II) ions in natural water is still a challenge to the researchers due to stringent and permissible limits set by World Health Organization (WHO). Herein, highly selective optical (absorbance and fluorescence modes) sensing probe for monitoring Hg(II) ions in synthetic urine and ground water has been successfully demonstrated using gold nanoparticles (AuNPs)/rhodamine B (RB)/hexanedithiol (HDT) nanocomposites system. The incorporation of RB and HDT on AuNPs improved sensitivity and selectivity (1.8 times) towards Hg(II) ions over other metal ions, respectively. The proposed mechanism involved in Hg(II) sensing in absorbance mode was based on aggregation of composites AuNPs, while fluorescence mode was based on the turn on fluorescence approach through release of RB from AuNPs/RB/HDT nanocomposites system via subsequent formation of Hg-HDT complex. The linear dynamic range for detection of Hg(II) ions using AuNPs/RB/HDT nanocomposite system, when tested in optimized colorimetric and fluorescence based analytical method adopted to the Hg(II) spiked urine and ground water samples exhibited detection limit of 1 ng mL(-1) (1 ppb) and 0.5 ng mL(-1) (0.5 ppb) using absorption and fluorescence mode, respectively, which were significantly comparable to those used in other developed Hg detection probes.

• 出版日期2018-7-15