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Amplified Fluorescence Turn-on Assay for Mercury(II) Based on Conjugated Polyfluorene Derivatives and Nanospheres

Published online by Cambridge University Press:  01 February 2011

Yusong Wang  and
Bin Liu
Yusong Wang
Affiliation:
cheliub@nus.edu.sg, National University of Singapore, Chemical and Biomolecular Engineering, Singapore, Singapore
Bin Liu
Affiliation:
g0500032@nus.edu.sg, National University of Singapore, Chemical and Biomolecular Engineering, Singapore, Singapore
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Abstract

Detection of mercury with high sensitivity and selectivity constitutes a significant research concern. Here, we report an amplified fluorescence turn-on assay for mercury(II) with an improved performance. This sensing system takes advantage of optically amplifying fluorescent conjugated polyfluorene derivatives and DNA immobilized silica nanospheres (NSs) in addition to the specific thymine- mercury(II)-thymine(T- Hg2+-T) interaction. The employment of ion-specific T- Hg2+-T coordination increases the melting temperature (Tm) of the double-stranded DNA (dsDNA) on the hybridized NS surface. After thermal washing at 45 °C, the Hg2+ treated sample (dsDNA-NS) was effectively differentiated from that treated with nonspecific ions through monitoring fluorescence emission of fluorescein (Fl) labeled target DNA remained on the NS surface. Finally, a cationic conjugated polyfluorene derivative (CCP) was introduced to electrostatically associate with the DNA molecules on the NS surface, resulting in an amplified Fl signal via fluorescence resonance energy transfer (FRET) from the CCP to the dye molecule. In comparison with the use of Fl alone as a signal reporter, the presence of CCP significantly enhances the detection fluorescence intensity, reduces false-positive signal, and improves the detection selectivity for mercury(II). Further improvement in the probe design could yield more efficient metal ion sensors, which have the potential to be operated at room temperature and for the detection of other metal ions besides mercury(II).

Keywords

sensorpolymerphotoemission
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1134: Symposium BB – Polymer-Based Smart Materials–Processes, Properties and Application , 2008 , 1134-BB05-01
Copyright
Copyright © Materials Research Society 2009

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References

REFERENCES

1. Harris, H. H., Pickering, I. J. and George, G. N., Science 301, 1203 (2003).Google Scholar
2. [2a] Clever, G. H., Kaul, C. and Carell, T., Angew. Chem. Int. Ed. 46, 6226 (2007);Google Scholar
[2b] Miyake, Y., Togashi, H., Tashiro, M., Yamaguchi, H., Oda, S., Kudo, M., Tanaka, Y., Kondo, Y., Sawa, R., Fujimoto, T., Machinami, T. and Ono, A., J. Am. Chem. Soc. 128, 2172 (2006).Google Scholar
3. Ono, A. and Togashi, H., Angew. Chem. Int. Ed. 43, 4300 (2004).Google Scholar
4. Liu, X., Tang, Y., Wang, L., Zhang, J., Song, S., Fan, C. and Wang, S., Adv. Mater. 19, 1471 (2007).Google Scholar
5. [5a] Lee, J. S., Han, M. S. and Mirkin, C. A.. Angew. Chem. Int. Ed. 46, 4093 (2007);Google Scholar
[5b] Xue, X., Wang, F. and Liu, X., J. Am. Chem. Soc. 130, 3244 (2008).Google Scholar
6. Liu, J. and Lu, Y., Angew. Chem. Int. Ed. 46, 7587 (2007).Google Scholar
7. Thomas, S. W., Joly, G. D. and Swager, T. M., Chem. Rev. 107, 1339 (2007).Google Scholar
8. Liu, B. and Bazan, G. C., Chem. Mater. 16, 4467 (2004).Google Scholar
9. Liu, B. and Bazan, G. C., J. Am. Chem. Soc. 126, 1942 (2004).Google Scholar
10. Wang, Y. and Liu, B., Chem. Commun. 34, 3553 (2007).Google Scholar
11. [11a] Gaylord, B. S., Heeger, A. J. and Bazan, G. C., Proc. Natl. Acad. Sci. USA. 99, 10954 (2002);Google Scholar
[11b] Wang, S., Gaylord, B. S. and Bazan, G. C., Adv. Mater. 16, 2127 (2004).Google Scholar
12. Aberem, M. B., Najari, A., Ho, H. A., Gravel, J. F., Nobert, P., Boudreau, D. and Leclerc, M., Adv. Mater. 18, 2703 (2006).Google Scholar
13. Liu, B. and Bazan, G. C., J. Am. Chem. Soc. 128, 1188 (2006).Google Scholar
14. Wang, Y. and Liu, B., Anal. Chem. 79, 7214 (2007).Google Scholar
15. We first investigate the sensing method by comparing Hg2+ incubation during hybridization and after hybridization. The results show that ∼14.1% PL intensity was retained after thermal washing (45 °C) for mercury incubation during hybridization. In contrast, ∼72.3% PL intensity was retained after thermal washing (45 °C) for mercury incubation after hybridization. Therefore, the sensing scheme of using mercury incubation after hybridization is selected for our Hg2+ assay.Google Scholar