Tunable fluorescent pH sensor
pH range of PTCAM entered into a significant physiological
References
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.
In the presence of other ligands, three-component PTCA/Fe3+/L
complexes were formed. Here triethylamine (L1), pyridine (L2) and
phenanthroline (L3) were used as ligands. Figure 2 also displays
I/Imax of 10À5 M PTCAM containing 10 equiv. of Fe3+ in a
2 Â 10À3 M phosphate buffer in the presence of 10À3 M different
ligands at different pH values. The sensors displayed a regular sig-
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was quenched because of formation of PTCA/Fe3+/L complexes.
The complexes were more stable than PTCA/Fe3+ complex and
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window. As in PTCA/Fe3+/pyridine system, the pH response ‘off’
(pH 6.0) and ‘on’ (pH 8.0) states could be easily distinguished by
eye (Fig. 2 inset). This near-neutral pH response range is very signif-
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Acknowledgements
This work was supported by the National Natural Science Foun-
dation of China (20771067) and Natural Science Foundation of
Shandong Province (2008BS02004).
Luminescence 2011
Copyright © 2011 John Wiley & Sons, Ltd.
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