title: An optical sensor for mercury ion based on the fluorescence quenching of tetra(p-dimethylaminophenyl)porphyrin.
abstract: An optical sensor for mercury ion (Hg(2+)), based on quenching the fluorescence of the sensing reagent porphyrin immobilized in plasticized poly(vinyl chloride) (PVC) membrane, has been developed. The responses to mercury ion were compared for the sensors modified with three porphyrin compounds including 5,10,15,20-tetraphenylporphyrin (TPP), tetra(p-dimethylaminophenyl)porphyrin (TDMAPP) and tetra(N-phenylpyrazole) porphyrin (TPPP). Among them, TDMAPP showed the most remarkable response to Hg(2+). The drastic decrease of the TDMAPP fluorescence intensity was attributed to the formation of a complex between TDMAPP and Hg(2+), which has been utilized as the fabrication basis of a Hg(2+)-sensitive fluorescence sensor. The analytical performance characteristics of the TDMAPP modified sensor was investigated. The response mechanism, especially involving the response difference of three porphyrin compounds, was discussed in detail. The sensor can be applied to the quantification of Hg(2+) with a linear range covering from 4.0x10(-8)molL(-1) to 4.0x10(-6)molL(-1). The limit of detection was 8.0x10(-9)molL(-1). The sensor exhibited excellent reproducibility, reversibility and selectivity. Also, the TDMAPP-based sensor was successfully used for the determination of Hg(2+) in environmental water samples.
authors.affiliation: State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China. yuyang@rcees.ac.cn
authors.forename: Yu
authors.initials: Y
authors.lastname: Yang
authors.forename: Jianhui
authors.initials: J
authors.lastname: Jiang
authors.forename: Guoli
authors.initials: G
authors.lastname: Shen
authors.forename: Ruqin
authors.initials: R
authors.lastname: Yu
mesh_terms: D004784:Environmental Monitoring; D005456:Fluorescent Dyes / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008628:Mercury / Q000032:analysis* / Q000737:chemistry; D011166:Porphyrins / Q000737:chemistry*; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D005456:Fluorescent Dyes; D011166:Porphyrins; D014874:Water Pollutants, Chemical; C540002:tetra(p-dimethylaminophenyl)porphyrin; D008628:Mercury