• 약학회지
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• 제39권1호
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• pp.61-67
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• 1995

PVC membrane electrodes based on the lipophilic neutral carrier, dibenzo-18-crown-6, cyclic oligomers of teit-butylphenol-formaidehyde condensates, calix[4]arenes as the active sensors for verapamil have been prepared and tested in a variety of plasticizers. At pH 5.0, the electrode exhibits a Nernstian response in the range of 10$^{-2}$~5$\times$10$^{-5}$ M verapamil with a slope of 49.1$\pm$0.5mV per concentration decade. The electrode constructed in this work can be used continuously for at least 1 month before any damage to the membrane occurs. And the analyses of the local anesthetic amine, which are good to select a specific compound in a mixed solution, were also accomplished by using of another neutral carrier, a DB18C6, for comparing with calix[4]arene.

• Bulletin of the Korean Chemical Society
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• 제24권12호
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• pp.1737-1741
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• 2003

Azo-functionalized calix[4]arenes as ionophores for chloride-selective electrode, 5,11,17,23-Tetra-tert-butyl-25,27-bis[(N,N-dimethyl-aniline-azo-phenylthioureido)ethyl]oxy-26,28-dihydroxycalix[4]arene (4a) and 5,11,17,23-Tetra-tert-butyl-25,27-bis[(N,N-dimethyl-aniline-azo-phenylthioureido)ethyl]oxy-26,28-dimethoxycalix[4]arene (4b) were synthesized. The PVC membrane electrode based on azo-functionalized calix[4]arene 4a with o-NPOE exhibits a linear stable response over a wide concentration range ($1.5{\times}10^{-4}-1.0{\times}10^{-1}$) with a slope of -52.0 mV/decade and a detection limit of log[$Cl^-$] = -4.02. This ionophore-based membrane exhibited improved selectivity for chloride anion compared with classical Hofmeister series.

• Bulletin of the Korean Chemical Society
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• 제23권10호
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• pp.1409-1412
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• 2002

Polymeric membrane electrodes for acetate anion based on meso-(${\alpha}$,${\alpha}$,${\alpha}$,${\alpha}$)-5,10,15,20-tetrakis[2-(penta-fluorophenylurea) phenyl]porphyrin I and similar urea-functionalized porphyrins Ⅱ-Ⅳ as neutral ionophores were prepared. The membrane based on porphyrin I exhibits the best potentiometric properties in pH 6.0 rather than pH 7.0: linear stable response over a wide concentration range (6.0 ${\times}$$10^{-5}$-1.0 ${\times}$$10^{-2}$) with a slope of -59.6 mV/decade and a detection limit of log[CH3CO$O^-$] = -5.32. Selectivity coefficients obtained from the matched potential method (MPM) in pH 6.0 indicate that interferences of hydrophobic anions are very small for the membranes of porphyrins I and II having the strong withdrawing group. The electronic effect of urea-functionalized porphyrins and pH effect of buffer solutions are discussed on the potentiometric response.

• Bulletin of the Korean Chemical Society
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• 제14권1호
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• pp.123-127
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• 1993

New lipophilic Crown-4 compounds of 16-membered rings containing furan (neutral carrier,I), tetrahydrofuran (neutral carrier,II) and lithium complex of the latter (neutral carrier,III) have been synthesized and tested as the active sensors for lithium ion in poly(vinyl chloride) (PVC) membrane electrode, in the presence and absence of an anion excluder, tetrakis(4-chloro-phenyl)borate (KTClPB), 2-nitrophenyl phenyl ether (NPPE), tris(2-ethylhexyl)phosphate (TEHP), o-nitrophenyl octyl ether (NPOE), dioctyl adipate (DOA), bis(2-ethylhexyl)adipate (BEHA), di-n-octylphenyl phosphonate (DOPP) were used as plasticizing solvent mediators. The electrode response function had a nearly Nernstian slope of 54-61 mV per decade (25$^{\circ}$C) within the concentration range of $10^{-1}-10^{-4}$ M LiCl and the detection limits for all electrodes were ca. $5{\times}10^{-4}$ M. The response time of the electrode was faster at the higher lithium concentration and the response of the electrode was stable for longer than 6 months. The sensor membranes exhibit improved response times and increased lifetimes as compared to the system described earlier.

• 분석과학
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• 제8권4호
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• pp.623-630
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• 1995

Silicone rubber-based sodium-selective membranes are developed for solid-state ion sensors. It was shown that the potetiometric performance of SR-based membranes are greatly dependent on the type of neutral carriers employed; among the three ionophores, N,N,N',N'-tetracyclohexyl-1,2-phenylenedioxydiacetamide (ETH 2120), bis[(12-crown-4)methyl]dodecylmethylmalonate (D12C4DMM) and monensin methyl ester (MME), examined, only ETH 2120 was compatible with the SR-based matrix. Addition of about 20 wt% plasticizer to the SR-based matrix provided the resulting membranes with potentiometric properties essentially equivalent to those of the corresponding PVC-based membranes. Owing to the strong adhesive strength of SR-based membranes, the CWEs coated \vith those membranes exhibited long lifetime with conventional electrode-like performance. Blending of PU into the SR matrix increased the lifetime of CWEs from two weeks to one month.

• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2229-2237
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• 2012

The two chelates based on calix[4]arene and thiacalix[4]arene have been synthesized and used as neutral ionophores for preparing PVC based membrane sensor selective to $Ho^{3+}$ ion. The addition of potassium tetrakis(4-chlorophenyl)borate (KTpClPB) and various plasticizers, viz., NDPE, o-NPOE, DOP, TEP and DOS have been found to improve significantly the performance of the sensors. The best performance was obtained with the sensor no. 6 having membrane of $L_2$ with composition (w/w) ionophore (2%): KTpClPB (4%): PVC (37%): NDPE (57%). This sensor exhibits Nernatian response with slope $21.10{\pm}0.3mV/decade$ of activity in the concentration range $3.0{\times}10^{-8}-1.0{\times}10^{-2}M\;Ho^{3+}\;ion$, with a detection limit of $1.0{\times}10^{-8}M$. The proposed sensor performs satisfactorily over a wide pH range of 2.8-10, with a fast response time (5 s). The sensor was also found to work successfully in partially non-aqueous media up to 25% (v/v) content of methanol, ethanol and acetonitrile, and can be used for a period of 4 months without any significant drift in potential. The electrode was also used for the determination of $Ho^{3+}$ ions in synthetic mixtures of different ions and the determination of the arsenate ion in different water samples.

• 대한화학회지
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• 제39권9호
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• pp.698-704
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• 1995

33중량%의 PVC와 66중량%의 o-NPOE 가소제에 1중량%의 중성 전극물질인 4'-benzothiazolyl-benzo-15-crown-5를 사용하여 성형한 막전극은 다른 15-크라운-5난 18-크라운-6 유토체들에 비하여 나트륨에 대하여 보다 낮은 선택성을 갖는 칼륨선택성을 나타내었다. 이 막전극의 전기화학적 성질들(감응기울기, 선택성, 섬출한계 및 수명)을 잘 알려져 있는 칼륨선택성 전극물질인 발리노마이신, benzo-15-crown-5, 4'-aminobenzo-15-15-crown-5, benzo-18-crown-6, dibenzo-18-crown-6 및 bis[(benzo-15-crown-5)-4'-ylnethuyl]pimelate를 사용한 전극막들의 것과 동일한 실험 조건하에서 비교하였다. 이러한 비교연구를 통하여 벤조티아졸기가 치환된 벤조크라운에테르 화합물이 증가된 칼륨이온 선택성을 나타내게되는 이유를 치환기의 효과와 이온의 분배계수효과로 설명하였다.

• 분석과학
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• 제13권4호
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• pp.466-473
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• 2000

용매고분자막 상에 칼륨과 다양한 나트륨이온 선택성 중성 운반체의 착물형성상수(${\beta}_{MLn}$)를 고분자막형 광센서(optode)와 이온선택성 전극(ISE)을 이용하여 결정하였다. 수소이온선택성 발색물질(chromoionophore : ETH 5294)에 가장 널리 쓰이는 나트륨 이온선택성 물질들(4-tert-butylcalix[4]arenetetraacetic acid tetraethyl ester, ETH 2120, bis[(12-crown-4)methyl] dodecyl-methylmalonate 및 monensin methyl ester)을 첨가한 막과 첨가하지 않은 막으로 두 가지 다른 조성의 PVC 막을 제작하여, 일정 pH(0.05 M Tris-HCl, pH7.2)에서 알칼리금속 양이온(나트륨과 칼륨)의 농도 변화에 따른 광학적 감응을 측정하고, 또 일정한 알칼리금속 양이온 농도(0.1M)에서 pH변화에 따른 광학적 감응을 측정하였다. 또한 유사한 조성의 막을 각각 재래식 전극체에 장착하고 일정한 알칼리금속 양이온의 농도(0.1M)에서 pH 변화에 따른 전위치를 측정하였다. 양이온/수소이온의 활동도 비($a_{M^+}/a_{H^+}$)와 상대흡광도로 도시한 광센서 감응곡선과 수소이온농도에 따른 전위차 감응곡선으로부터 나트륨 이온선택성 리간드들의 착물형성상수를 결정하였다. 목적이온과 방해이온에 대한 착물형성상수들의 비로부터 얻어진 값은 실험적으로 얻어진 이온선택성 전극의 선택계수와 근접함을 확인하였다.