1998 Fiscal Year Final Research Report Summary
Molecular Design of Alkali Metal Ion Probes for Use in Aqueous Media
| Project/Area Number |
09650893
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
工業分析化学
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| Research Institution | Tohoku University |
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Principal Investigator |
HAYASHITA Takashi Tohoku University Dept.of Chem.Associate Professor, 大学院・理学研究科, 助教授 (70183564)
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| Co-Investigator(Kenkyū-buntansha) |
TAKAGI Makoto Tohoku University Dept.of Mol.Chem.Professor, 大学院・工学研究科, 教授 (90037739)
NISHIZAWA Seiichi Tohoku University Dept.of Chem.Research Associate, 大学院・理学研究科, 助手 (40281969)
UCHIDA Tatsuya Tohoku University Dept.of Chem.Research Associate, 大学院・理学研究科, 助手 (30261548)
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| Project Period (FY) |
1997 – 1998
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| Keywords | Chromoionophore / Fluoroionophore / Crown Ether / Micelle / Cyclodextrin / Alkali Metal Ion / Sensing / Aqueous Media |
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| Research Abstract |
A selective colorimetry of alkali metal cations in aqueous micellar solution containingsym-(alkyyl)(2-hydroxy-5-nitrobenzyloxy)dibenzo-1 6-crown-5 (1) has been examined. Colorimetric behavior were found to be strongly affected by the surface charge of micellar species and a selective colorimetry of Na^+ was performed in the anionic micellar solution containing lipophilic DB 16C5 chromoionophore. By introducing pyrenecarboxamide unit into DB16C5 skeleton (2), a fluorescent response for Na^+ binding is expected. It was found that proton dissociation of the carboxamido moiety in fluoroionophore was promoted by Na^+ binding, which resulted in an efficient ratiometric emission due to internal charge transfer (ICT) from the donorcarboxamido anion to the pyrene acceptor. No fluorescent response was induced by the presence of Li^+ or Cs^+. Thus fluoroionophore 2 exhibited a dual emission response with high Na^+ selectivity in 4 : 1 1 , 4-dioxane-water (v/v). The benzo-15-crown-5 (B15C5) fluoroionophore 3 can be classified as a photoinduced electron transfer (PET) sensor. A moderate Na^+ selectivity is obtained for 3 based on a 1 : 1 complex formation ability of the B 1 5C5 moiety in a non-aqueoussolution. In contrast, 3 was found to work as a novel ion probe in the presence of gamma-CyD, and it achieved high sensitivity and selectivity for K^+ even in the presence of Na^+. The results revealed that 3 formed a 2 : 1 complex with high selectivity for K^+ in the presence of gamma-CyD, and it exhibited both monomer and dimer emission in water.
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