• Bulletin of the Korean Chemical Society
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• 제24권11호
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• pp.1585-1589
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• 2003

A PVC-based membrane electrode for thallium(I) ions based on 1,21,23,25-tetramethyl-2,20: 3,19-dimetheno-[H, 2] H, 23H, 25H-bis-[1,3] dioxocino[5,4-i:5',4'-i] benzo [1,2-d: 5.4-d'] bis [1,3] benzodioxocin(II) has been prepared. The electrode displays a linear dynamic range of $1.0{\times}10^{-1}-1.0{\times}10^{-5}$ M, with a Nernstian slope of $59.8{\pm}0.2\;mV\;{decad^-1}$, and a detection limit $5.0{\times}10^{-6}$ M. It has a very fast response time of<10 s and can be used for at least ten weeks without a considerable divergence in potentials. This electrode revealed comparatively good selectivity with respect to alkali, alkaline earth, and some transition and heavy metal ions and was effective in a pH range of 2.0-10.0. It was used as an indicator electrode in potentiometric titration of thallium ion with sulfide ion.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.548-552
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• 2005

The interaction between ionic surfactants and different nonionic molecules and polymers are studied using ion surfactant selective electrode. From the experimental data, critical concentrations of the interaction and binding process are evaluated. The interaction between hexadecyltrimethylammonium bromide (HTAB) with polyethylene glycol (PEG) in three molecular weights (1000, 10000 and 100000) and also schiff-bases, 2-[2-carboxyphenyl nitrilomethylidyne]-phenol (ortho CNP), 2-[3-carboxyphenyl nitrilomethylidyne]-phenol (meta CNP)and 2-[4-carboxyphenyl nitrilomethylidyne]-phenol (para CNP) with the potentiometric method were investigated using HTAB membrane selective electrode. In the case of PEG with increasing molecular weights more interaction to HTAB occurs. The electromotive force (EMF) data also showed that interaction between para CNP with HTAB is more than the other schiff-bases. It seems this case related to less space interference of COOH group for that compound. The onset of binding ($T_1$) of course is the same for three schiffbase molecules.

• 한국안전학회지
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• 제9권1호
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• pp.68-75
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• 1994

The cetylpyridium ion-selective electrode were developed by dibenzo-18-crown-6 for auto control of the chemical plants. The effect of content of active material and the membrane thickness on the response characteristics of electrode such as the linear reponse range, the detection limit, and Nemstian slope of the electrod, were studied. The electrode characteristics was better with decreasing the content of active material above the optimum content, but became worse below these. DBP was best as a plasticizer, The effect of the membrane thickness on the electrode characteristics was improved with decreasing the membrane thickness, but below the optimum membrane thickness the electrode exhibited an inverse trend.

• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.3088-3092
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• 2013

A novel PVC membrane sensor for perindopril based on perindopril-phosphotungstate ion pair complex was prepared. The influence of membrane composition (i.e. percent of PVC, plasticizer, ion-pair complex, and kind of plasticizer), inner solution, pH of test solution and foreign cations on the electrode performance was investigated. The optimized membrane demonstrates Nernstian response ($30.9{\pm}1.0$ mV per decade) for perindopril cations over a wide linear range from $9.0{\times}10^{-7}$ to $1{\times}10^{-2}$ M at $25^{\circ}C$. The potentiometric response is independent of the pH in the range of 4.0-9.5. The proposed sensor has the advantages of easy preparation, fast response time. The selectivity coefficients indicate excellent selectivity for perindopril over many common cations (e.g., $Na^+$, $K^+$, $Mg^{2+}$, $Cu^{2+}$, $Ni^{2+}$, rhamnose, maltose, glycine and benzamide. The practical applications of this electrode was demonstrated by measuring the concentrations of perindopril in pure solutions and pharmaceutical preparations with satisfactory results.

• 분석과학
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• 제8권2호
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• pp.187-193
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• 1995

N,N,N,N-Tetrabenzylethylenediamine 중성운반체를 이용하여 PVC 수소이온 선택성 막전극을 제조하였다. 가소제 종류(phthalates와 sebacate) 및 친지방성 첨가제(NaTPB)에 따른 막전극의 전기저항과 수소이온 감응범위 및 알칼리금속과 알칼리토금속의 존재하에서 방해효과를 조사하였다. 가소제 종류에 의한 전기저항은 영향을 거의 받지 않았고 NaTPB 0.7%의 경우 수소이온에 대한 Nernstian 기울기는 가장 이론값에 근접하였으며, 또한 알칼리금속 및 알칼리토금속에 의한 방해도 적게 받았다. pH-선택성 고분자 막전극은 pH 2~10 범위내에서 선형적이고, 산과 알칼리용액 중에서 안정성 및 재현성 시험 결과 매우 좋게 나타났다.

• 한국응용과학기술학회지
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• 제30권2호
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• pp.356-361
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• 2013

Lead (II) ion selective poly(aniline) solid contact electrode based on Tetramethylthiuram monosulfide ionophore as a sulfur containing sensing material is successfully developed. The electrode exhibits good linear response of 25.6 mV / decade (at $20{\pm}0.2^{\circ}C$, r2=0.995) within the concentration range of $1.0{\times}10^{-1}{\sim}4.0{\times}10^{-7}$ M Pb (II). The composition of this electrode was Ionophore : PVC : dioctylphthalate : potassiumtetrakis(4-chlorophenyl)borate : Oleic acid = 5.0 : 20.0 : 25.0 : 4.0 : 5.0. When we consider the results of using different composition electrodes based on only one potassiumtetrakis(4-chlorophenyl)borate or Oleic acid liphophlic additive, poly(aniline) solid contact electrode based on Tetramethylthiuram monosulfide ionophore with potassiumtetrakis(4-chlorophenyl)borate and Oleic acid liphophlic additive had the best result in response characteristics. The electrode shows good selectivity for lead (II) ion in comparison with alkali, alkaline earth, transition and heavy metal ions. This electrode is suitable for use with aqueous solutions of pH 3.0 ~ 7.0 and their standard deviation in the measured emf differences was ${\pm}2.94$ mV at Tris buffered lead sample solution of $1.0{\times}10^{-2}$ M and ${\pm}2.82$ mV at Tris buffered lead sample solution of $1.0{\times}10^{-3}$ M. Their stabilization time was less than 710 s. and response time was less than 16 s.

• Bulletin of the Korean Chemical Society
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• 제35권11호
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• pp.3175-3180
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• 2014

A potentiometric sensor based on the 1-benzyl-3-(4-nitrophenyl) thio-urea was synthesized and tested as an ionophore in PVC based membrane sensor towards $SCN^-$ ions. This membrane exhibits a linear stable response over a wide concentration range ($1.0{\times}10^{-5}$ to $1.0{\times}10^{-2}M$) with a slope of -59.2 mV/dec., a detection limit of ${\log}[SCN^-]=-5.05$, and a selectivity coefficient for thiocyanate against perchlorate anion of ${\log}K^{pot}_{SCN^-j}=-0.133$. The selectivity series of the membrane is as follows: $SCN^-$ > $ClO_4{^-}$ > $I^-$ > $NO_3{^-}$ > $HSO_3{^-}$ > $Cl^-$ > $HSO_4{^-}$ > $F^-$ > $CH_3COO^-$ > $HCO_3{^-}$ > $Br^-$ > $H_2PO_4{^-}$ > $SO{_3}^{2-}$ > $SO{_4}^{2-}$ > $CO{_3}^{2-}$. The proposed electrode showed good selectivity and a good response for the $SCN^-$ ion over a wide variety of other anions in pH 6.0 buffer solutions and has a fast response time of about < 5s. The influences of the membrane by pH, ionophore, and plasticizer were studied.

• 공업화학
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• 제9권5호
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• pp.734-741
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• 1998

본 연구에서는 전극전위 분석법을 사용하여 중성운반체로 dibenzo-18-crown-6(D18Cr6)와 valinomycin(Val)을 이용하여 $K^+$ 이온선택성 PVC막 전극의 막과 용액계면에서의 전극특성을 검토하였다. PVC막에서 감응물질(운반체)에 기본전해질의 혼입 (doping)여부, 감응물질의 종류와 함량, 가소제, 막두께 및 이온의 활동도변화에 따른 전극의 기울기, 선형응답범위 한계측정농도 및 방해이온에 따른 선택계수 등 전극특성을 검토하였다. 중성운반체로 D18Cr6, Val을 $K^+$ 이온으로 착체형성하여 사용하였고, 가소제로 dibutylphthalate(DBP), dioctyl sebacate(DOS) 및 dibutyl sebacate(DBS)를, 혼입제인 기본전해질로 potassium tetraphenylborate (KTPB) 및 용매로 THF를 지지체로 PVC를 이용하여 막을 제조하였다. 운반체의 최적 함량은 D18Cr6와 Val의 경우 3.23 wt %이었고, 가소제는 DBP가 가장 적절한 가소제이었다. 막두께에 대한 영향은 최적 막두께 이상에서는 막두께가 얇아질수록 전극특성이 좋아졌으나, 막두께가 이 이하로 얇아지면 운반체의 용출, 막의 강도 등이 작용하여 전극특성이 나빠짐을 알 수 있었다. D18Cr6의 경우 $K^+$ 이온에 대한 혼합용액법에 의한 선택계수 서열은 다음과 같았다: $NH_4{^+}>Ca^{2+}>Mg^{2+}>Na^+$.

• 대한화학회지
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• 제55권1호
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• pp.63-69
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• 2011

이 작업은 수송체로서 N,N'-bis(2-hydroxybenzyl)-1,3-diaminopropane (L1)과 N,N'-bis(2-hydroxybenzyl)-2,2-dimethyl-1,3-diaminopropane (L2)에 기초한 $Ag^+$ 이온-선택 전극의 제조, 개발 그리고 전압반응에 대해 토의한다. $Ag^+$에 대하여 L1에 기초한 전극은 58.7 mV/dec에 도달하는 안정한 Nernst에 가까운 기울기와 $1.0{\times}10^{-6}M$의 검출한계를 갖는 등급의 최소 다섯가지 순서의 선형범위에서 최적의 전압 반응 특징을 보이는 것을 나타낸다. 제안된 전극은 다른 테스트한 양이온과 비교하여 $Ag^+$에 우위의 선택성을 보였다. 훌륭한 전압 분석적 특징은 중요한 진짜 샘플에서 은의 순도분석의 성공적인 응용을 이끌 것이다. 그리고 그것은 제안된 $Ag^+$-ISE가 측정 능력의 중요한 진보를 보여준다는 것을 나타내고 있다. 그러나 L2에 기초한 전극에 대해서는, 약한 전압 반응 특징들이 전체 실험 과정에서 관측되었다.

• Bulletin of the Korean Chemical Society
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• 제25권3호
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• pp.361-364
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• 2004

The potentiometric response of electrode no. 4 based on 1,3-bisbridged cofacial-calix[6]crown-5-ether (IV) gave a sub-Nernstian (45.0 mV/decade) response and the best detection limit (-log $a_{ep}$ = 4.73) towards epinephrine. The responses are decreasing in the order of epinephrine > $K^+$, dopamine > $NH_4^+$ > norepinephrine > $Na^+$. It is remarkable that the proposed electrode shows the reasonable selectivity to epinephrine against other catecholamine neurotransmitters (dopamine and norepinephrine) as well as alkali metal ions.