Recyclable fluorimetric and colorimetric mercury-specific sensor using porphyrin-functionalized Au@SiO2 core/shell nanoparticlesElectronic supplementary information (ESI) available: Measurement data. See DOI: 10.1039/c0an00137f
A fluorimetric/colorimetric mercury sensor based on Au@SiO 2 core/shell nanoparticles has been developed and demonstrated. The porphyrin derivative ( 2 ) was attached to Au@SiO 2 core/shell nanoparticles by covalent bonds and showed a red color and strong fluorescent properties. In the absence of sp...
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Main Authors | , , |
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Format | Journal Article |
Language | English |
Published |
21.06.2010
|
Online Access | Get full text |
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Summary: | A fluorimetric/colorimetric mercury sensor based on Au@SiO
2
core/shell nanoparticles has been developed and demonstrated. The porphyrin derivative (
2
) was attached to Au@SiO
2
core/shell nanoparticles by covalent bonds and showed a red color and strong fluorescent properties. In the absence of specific metal ions, the porphyrin-functionalized Au@SiO
2
nanoparticles (
1
) exhibited strong fluorescence emission and were red in color. The addition of Hg
2+
ion to
1
resulted in a color change from red to green within 10 s and a weak display of fluorescence. Conversely, no significant changes in fluorescence emission or color were observed in the parallel experiments with Li
+
, Na
+
, Ca
2+
, Cu
2+
, Cd
2+
, Co
2+
, Mn
2+
, Cd
2+
, Ag
+
and Pb
2+
. Regarding the reversibility of
1
, the fluorescence and color of
1
in the presence of Hg
2+
ion were found to be almost reversible when
1
was treated with EDTA solution. Furthermore, a study of the effect of pH on
1
with bound Hg
2+
ion indicated that the fluorescence intensity and color change of
1
was almost constant between pH 4 and 10. This sensor has excellent selectivity and sensitivity over other metal ions and has detection limits below the maximum contamination level of 1.2 ppb for Hg
2+
ion in drinking water, as defined by the U. S. Environmental Protection Agency (EPA). The results obtained not only allow a practical sensing application for the Hg
2+
ion but also serve as a guide for the design of fluorimetric/colorimetric sensors for other targets.
Porphyrin derivative immobilized Au@SiO
2
core/shell nanoparticle (
1
) recognized and separated Hg
2+
with a high degree of selectivity among heavy metal ions in aqueous solution. |
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Bibliography: | 10.1039/c0an00137f Electronic supplementary information (ESI) available: Measurement data. See DOI |
ISSN: | 0003-2654 1364-5528 |
DOI: | 10.1039/c0an00137f |