螢光性共軛高分子是極重要的金屬離子感測性材料，本研究利用Suzuki聚合反應合成出側鏈帶有羧基 (-CH2CH2COO-Na+)的聚芴高分子P1以及主鏈摻入芳香噁二唑的高分子P2，探討其光學性質及感測特性，此類高分子可以溶於水醇類等高極性溶劑，在溶液態的吸收和放光皆和聚芴相似，分別位於在385 nm與430 nm附近。
其次探討在中性條件下P1及P2對金屬的辨識能力以及形成錯合物的機制，當加入亞銅離子 (Cu+)及銅離子 (Cu2+)後，P1及P2螢光光譜產生明顯的淬熄，P1對Cu+及Cu2+的Stern-Volmer係數 (Ksv)值高達3.5×106及5.78×106 M-1，推測是銅離子造成聚集誘導 (aggregation-induced)之螢光淬熄，而由Job’s Plot得知高分子P1與亞銅離子及銅離子形成錯合物的配位比均為2:1，與文獻指出銅離子與羧基易形成的4配位數相符合。在其它的金屬離子的干擾之下，P1對亞銅離子及銅離子仍具有極佳的選擇性。在酸性環境下，因P1之COOH基團間產生強氫鍵而形成聚集，導致其螢光淬熄 (相對於中性溶液之螢光)，但在鹼性環性下，由於COO-間的電荷排斥力使聚集現象減弱，因而產生螢光增強的現象。另外，在酸性、鹼性條件下加入Cu2+只產生些微淬熄，且加入EDTA後其螢光光譜具有完全可逆性，但中性狀態下如上所述產生明顯的淬熄，加入EDTA時螢光的回復性不佳。
研究結果發現，P1對Cu+及Cu2+具有極高的敏感性與選擇性，未來有潛力成為Cu+及Cu2+的有效感測器。

Fluorescent conjugated polymers are important chemosensory materials for metal ions. However, the solubility of conjugated polymers is usually too low to be applied in aqueous solutions. We have synthesized two water-soluble conjugated polymers (carboxylated polyfluorenes P1, P2) by the Suzuki coupling reaction to investigate their chemical sensory characteristics. Poly[9,9’-bis(3’’-propanoate)fluoren-2,7-yl] sodium salt (P1) and its copolymer with 1,3,4-oxadiazole (P2) were dissolved in aqueous solutions, their absorption and fluorescence variations in the presence of various metal cations and under different pH were investigated to evaluate their sensory properties.
The recognition ability of P1 and P2 to various metal ions was then studied and their mechanism in complex formation was proposed accordingly. The fluorescence spectra of neutral aqueous solutions of P1 and P2 were significantly quenched in the presence of Cu+ and Cu2+. The fluorescence responses of P1 and P2 are very similar that the discussion is focused on P1’s results. The sensitivity of P1 to Cu+ and Cu2+ are very high, with the Stern-Volmer constants (Ksv) being 3.5×106 and 5.78×106 M-1, respectively. The fluorescence quenching has been attributed to polymer aggregation induced by copper ion. Moreover, the ratios of P1 repeat unit over Cu+ or Cu2+ were 2:1 obtained from the Job’s plot, indicating that copper ions are coordinated with four carboxyl groups. In addition, P1 shows high selectivity to Cu+ or Cu2+ in the presence of various metal ions.
Under acidic conditions, the fluorescence of neat P1 is significantly quenched, which is caused by the formation of aggregation due to strong hydrogen bonding between COOH groups. However, under basic conditions the fluorescence is enhanced due to reduced aggregation resulting from repulsion between COO- groups. In addition, under acidic and basic conditions the fluorescence quenching of P1 by Cu2+ is slight; but it is reversible by adding excess EDTA. However, in neutral aqueous solutions the quenching is significant; and the fluorescence recovers only slightly by EDTA, suggesting that P1’s COOH groups compete with EDTA in coordinating with Cu2+.
Our results demonstrate that P1 shows very high sensitivity and selectivity in recognizing Cu+ and Cu2+. Its potential application as chemical sensor for Cu+ and Cu2+ can be expected.

1.McQuade, D. T.; Pullen, A. E.; Swager, T. M. Chemical Reviews 2000, 100, 2537–2574.
2.Clark, L. C., Jr; LYONS, C. Ann. N. Y. Acad. Sci. 1962, 102, 29–45.
3.吳知易，國立成功大學化學工程研究所博士論文 (2005).
4.Pinto, M. R.; Schanze, K. S. Proceedings of the National Academy of Sciences of the United States of America 2004, 101, 7505–7510.
5.Thomas, S. W.; Joly, G. D.; Swager, T. M. Chemical Reviews 2007, 107, 1339–1386.
6.Chen, L.; McBranch, D. W.; Wang, H.-L.; Helgeson, R.; Wudl, F.; Whitten, D. G. PNAS 1999, 96, 12287–12292.
7.Kumaraswamy, S.; Bergstedt, T.; Shi, X.; Rininsland, F.; Kushon, S.; Xia, W.; Ley, K.; Achyuthan, K.; McBranch, D.; Whitten, D. PNAS 2004, 101, 7511–7515.
8.Adam, H.; Stanislaw, G.; Folke, I. Pure Appl Chem 1991, 63, 1274–1250.
9.Cammann, K.; Lemke, U.; Rohen, A.; Sander, J.; Wilken, H.; Winter, B. Angewandte Chemie International Edition in English 1991, 30, 516–539.
10.Valeur, B.; Leray, I. Coordination Chemistry Reviews 2000, 205, 3–40.
11.Schemehl, R. H.; Li, C. J.; Xia, W. S.; Mague, J. T.; Luo, C. P.; Guldi, D. M. J. Phys. Chem. B. 2002, 106, 833.
12.Masilamani, D.; Lucas, M. E. In Fluorescent Chemosensors for Ion and Molecule Recognition; Czarnik, A. W., Ed.; American Chemical Society: Washington, DC, 1992.
13.In Fluorescent Chemosensors for Ion and Molecule Recognition; Czarnik, A. W.; Comstock, M. J.; Comstock, M. J., Eds.; American Chemical Society: Washington, DC, 1993; Vol. 538, pp. i–vi.
14.Lee, J. W.; Jung, H. S.; Kwon, P. S.; Kim, J. W.; Bartsch, R. A.; Kim, Y.; Kim, S.-J.; Kim, J. S. Organic Letters 2008, 10, 3801–3804.
15.In Fluorescent Chemosensors for Ion and Molecule Recognition; Czarnik, A. W.; Comstock, M. J.; Comstock, M. J., Eds.; American Chemical Society: Washington, DC, 1993; Vol. 538, pp. i–vi.
16.De Silva, A. P.; Gunaratne, H. Q. N.; Gunnlaugsson, T.; Huxley, A. J. M.; McCoy, C. P.; Rademacher, J. T.; Rice, T. E. Chem. Rev. 1997, 97, 1515–1566.
17.Eggins, B. R. Biosensors-An Introduction, John Wiley ＆Sons: Chichester, 1997.
18.Marquis, D.; Desvergne, J.-P. Chem. Phys. Lett. 1994, 230, 131–136.
19.Bryan, A. J.; De Silva, A. P.; De Silva, S. A.; Rupasinghe, R. A. D. D.;
Sandanayake, K. R. A. S. Biosensors. 1989, 4, 169.
20.Bissell, R. A.; De Silva, A. P.; Gunaratne, H. Q. N.; Lynch, P. L. M.;
Maguire, G. E. M.; Sandanayake, K. R. A. S. Chem. Soc. Rev. 1992, 21,
187.
21.Bergonzi, R.; Fabbrizzi, L.; Licchelli, M.; Mangano, C. Coord. Chem. Rev. 1998, 170, 31–46.
22.De Silva, A. P.; De Silva, S. A. J. Chem. Soc., Chem. Commun. 1986,
1709-1710
23.Desvergne, J. -P.; Czarnik, A. W. Chemosensors for Ion and Molecule Recognition, NATO ASI Ser., 492, Kluwer﹕ Dordrecht, 1997.
24.Scherer, T.; van Stokkum, I. H. M.; Brouwer, A. M.; Verhoeven, J. W. J. Phys. Chem. 1994, 98, 10539–10549.
25.J. R. Lakowicz. Principles of fluorescence spectroscopy, 2nd ed, Plenum Publishers, New York, 13, 1999.
26.Lavigne, J. J.; Broughton, D. L.; Wilson, J. N.; Erdogan, B.; Bunz, U. H. F. Macromolecules 2003, 36, 7409–7412.
27.Che, Y.; Yang, X.; Zang, L. Chem. Commun. 2008, 1413.
28.Tanzi, T. E. et al. Nature Genet. 1993, 5, 344–350.
29.Vulpe C. , L evington. B., W hitney S. , et al., Nature Genet. 1993, 3, 7– 13.
30.Li, J.; Guo, Y.; Yao, H.; Lin, Q.; Xie, Y.; Wei, T.; Zhang, Y. Chin. J. Chem. 2013, 31, 271–276.
31.Wu, J.-S.; Wang, P.-F.; Zhang, X.-H.; Wu, S.-K. Spectrochim. Acta. A. Mol. Biomol. Spectrosc. 2006, 65, 749–752.
32.Xu, Y.; Lu, F.; Xu, Z.; Cheng, T.; Qian, X. Sci. China Ser. B Chem. 2009, 52, 771–779.
33.D. A. Skoog, F. J. Holler, T. A. Nieman, Principles of Instrumental analysis 5th ed, Harcourt Brace & Co. , 1998.
34.Joseph R. Lakowicz, Principle of Fluorscence Spectroscopy, 3rd Ed. Springer, Vol. 1. 2006.
35.Miyaura, N.; Suzuki, A. Chem. Rev. 1995, 95, 2457–2483.
36. D. A. Skoog, D. M. West, F. J. Holler, Stnaley R. Crouch, Fundamentals of Analytical Chemistry, Saunders, 2000, pp. 458-471.
37.藍婉珊，國立台南大學自然科學教育學系碩士論文 (2006)
38.T. Ishiyama, M. Murata, N. Miyaura, J. Org. Chem. 1995, 60, 7058–
7062.
39.Chen, S.-H.; Chen, Y. Macromolecules 2005, 38, 53–60.