• Bulletin of the Korean Chemical Society
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• 제22권4호
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• pp.405-408
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• 2001

New lipophilic triesters of calix[4]arene and calix[4]quinone are investigated as sodium ion-selective ionophores in poly(vinyl chloride) membrane electrodes. For an ion selective electrode based on calix[4]arene triester I, the linear response is 1 ${\times}$10-3.5 to 1 ${\times}$ 10-1 M of Na+ concentrations. The selectivity coefficients for sodium ion over alkali metal and ammonium ions are determined. The detection limit (logaNa+ = -4.50) and the selectivity coefficient (logKNa+,K+pot = -1.86) are obtained for polymeric membrane electrode containing calix[4]arene triester I.

• Bulletin of the Korean Chemical Society
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• 제22권12호
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• pp.1345-1349
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• 2001

New quadruply-bridged calix[6]arenes (I-V) have been studied as cesium selective ionophores in poly(vinyl chloride) (PVC) membrane electrodes. PVC membranes were prepared with dioctyl sebacate (DOS) or 2-nitrophenyl octyl ether (o-NPOE) as the sol vent mediator and potassium tetrakis(p-chlorophenyl)borate as the lipophilic salt additive. These ionophores produced electrodes with near-Nernstian slope. The selectivity coefficients for cesium ion with respect to alkali, alkaline earth and ammonium ions have been determined. The lowest detection limit (logaCs+ = -6.3) and the higher selectivity coefficient (logkpotCs+,Rb+ = -2.1 by SSM, -2.3 by FIM for calix[6]arene I) for Cs+ have been obtained for membranes containing quadruply-bridged calix[6]arenes (I, Ⅱ, Ⅲ), which have no para t-butyl substituents on the bridging benzene ring.

• Bulletin of the Korean Chemical Society
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• 제24권1호
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• pp.109-112
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• 2003

• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3509-3510
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• 2010

• 대한화학회지
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• 제42권5호
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• pp.531-538
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• 1998

캘릭스[4]아렌 유도체(호스트 1)를 이온선택성 물질로 사용하고, 지지체로 poly(vinyl chloride)(PVC), 가소제로 dioctylsebacate(DOS)를 사용하여 이온 선택성 막전극을 제작하였다. 호스트 1 막전극을 지시전극으로 사용하여 알칼리, 알칼리 토금속 양이온 그리고 전이 금속 양이온에 대하여 각각의 감응전위를 측정한 결과, 바탕 전해질이 탈 이온수 일때 $Pb^{2+}$의 감응전위가 $1.0 \times10^-6M~1.0 \times 10^-1 M$ 농도 범위에서 이론적인 Nernstian 감응전위 기울기에 가까운 26.5mV/decade를 보여 주었다. 또한 pH 영향을 조사해 본 결과 pH 4.00∼12.00 범위에서 감응전위값이 일정하게 유지되었다. 따라서 본 연구에서 제작된 호스트 1 막전극은 탈이온수 상에서 $Pb^{2+}$에 친화성을 갖는 이온 막전극으로 나타났다.

• Bulletin of the Korean Chemical Society
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• 제24권1호
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• pp.37-44
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• 2003

We examined the effect of polyether-type nonionic surfactants (Brij 35, Triton X-100, Tween 20 and Tween 80) on the potentiometric properties of sodium-, potassium- and calcium-selective membranes which are prepared with widely used ionophores and four kinds of polymer matrices [poly(vinyl chloride) (PVC), polyurethane (PU), PVC/PU blend, and silicone rubber (SR)]. It was found that the PVC-based membranes, which provide the best performance among all other matrix-based membranes in the absence of nonionic surfactants, exhibited larger change in their potentiometric properties when nonionic surfactants are added to the sample solution. On the other hand, the sodium-selective SR-based membrane with calix[4]arene, potassium-selective PVC/PU- or SR-based membrane with valinomycin, and the calcium-selective SR-based membrane with ETH 1001 provide almost identical analytical performance in the presence and absence of Tween 20 or Tween 80 surfactants. The origin of nonionic surfactants effect was also investigated by interpreting the experimental results obtained with various matrices and ionophores. The results suggest that the nonionic surfactant extracted into the membrane phase unselectively form complexes with the primary and interfering ions, resulting in increased background potential and lower binding ability for the ionophore. Such effects should result in deteriorated detection limits, reduced response slopes and lower selectivity for the primary ions.