• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1127-1132
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• 2006

A new salicylate-selective electrode based on the complex N,N'-1,4-butylene bis(3-methyl salicylidene iminato) copper(II) as the membrane carrier was developed. The electrode exhibits a good Nernstian slope of 59.1 ${\pm}$ 1.0 mV/decade and a linear range of $1.0\;{\times}\;10^{-6}$-1.0 M for salicylate. The limit of detection was $5.0\;{\times}\;10^{-7}$ M. It has a fast response time 10 s and can be used for more than three months. The selective coefficients were determined by the fixed interference method (FIM) and could be used in the pH range 4.5-10.5. It was employed as an indicator electrode for direct determination of salicylate in pharmaceutical samples.

• Bulletin of the Korean Chemical Society
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• 제28권12호
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• pp.2466-2470
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• 2007

A new highly salicylate-selective PVC membrane electrode based on tripodal tris-thiourea derivatives, L1 and L2, as neutral carriers is described. The electrodes display an excellent potentiometric response to salicylate ions and an anti-Hofmeister selectivity sequence in the following order: Salicylate? > ClO4 ? > Benzoate? > I? >NO3? > NO2? > Maleate? > Acetate? > Lactate? > Fumarate?. It also exhibited a near-Nernstian potential in a linear range of 5.0 × 10?5 - 1.0 × 10?1 M with a detection limit of 9.0 × 10?5 mol/L and a slope of ?59.9 mV/decade at a pH of 7.0 in a saline buffer solution at 25 oC. The stability constant (log KS) of the anionsionophore complex was also determined at 25 oC by a conductometric titration in DMSO solution.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1601-1608
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• 2010

A scandium(III) porphyrin-based fluoride-selective potentiometric sensor and its application in the analysis of hydrofluoric acid is described. Scandium(III) octaethylporphyrin, an ionophore recently developed for the optical fluoride sensor, was employed as a host molecule for the selective binding with fluoride in the plasticized PVC membrane. Nernstian response for $F^-$ between $10^{-4.6}$ to $10^{-1}$ M was observed at a glycine-phosphate buffer (pH 3.0). The selectivity pattern was observed as $F^-$, salicylate $\gg$ $SCN^-$ > $Cl^-$, $Br^-$, $NO_3{^-}$, $ClO_4{^-}$, which is consistent with the binding constant data measured in the plasticized PVC membrane based on a sandwich membrane method. This highly selective and reversible fluoride-sensitive electrode was employed for the analysis of hydrofluoric acid (HF). A disposable differential-type HF sensor was fabricated on the screen-printed electrode and demonstrated its ability to detect the neutral HF in the acidic solution.

• Bulletin of the Korean Chemical Society
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• 제25권10호
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• pp.1484-1488
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• 2004

The thiocyanate-selective PVC membrane electrodes based on 5,10,15,20-tetrakis(2,4,6-trimethylphenyl)-porphyrinatomanganese(III) chloride [Mn(TMP)Cl] and 5,10,15,20-tetrakis(2,6-dichlorophenyl)porphyrinatomanganese(III) chloride $[Mn(Cl_8TPP)Cl]$ as ion carriers were investigated. The effect of ionophores, membrane compositions, plasticizers, and solution pHs on the response characteristics were studied. The Mn(TMP)Cl as an ionophore shows the best potentiometric sensitivity with a slope of -58.7 mV/decade and a detection limit of $log[SCN^-]$ = -6.90, and selectivity for thiocyanate over strong hydrophobic interfering anions such as ${ClO_4}^-$ and salicylate. The potentiometric response is affected by the electronic effect of the substituents and solution pHs. The presence of substituents with electron donating and more liphophilic characters around the ligated metal center produces an improved response toward $SCN^-$.

• 대한화학회지
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• 제41권12호
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• pp.653-660
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• 1997

Tetradecyltrimethylammonium chloride(TDTMACl)을 첨가한 실리콘러버-지지체 전극막은 생체시료중 염화이온의 측정시 보다 향상된 전기화학적 특성을 나타내기 위하여 사용되었다. 이때 최적화된 전극막의 조성비는 95.4 wt% 실리콘러버, 4.6 wt% TDTMACl이며 이 전극막의 pH 감응성은 pH 6-10 영역에서 무시할 수 있었다. 이들 전극막들의 염화이온에 대해 감응기울기는 10-300 mM 영역에서 -3.75 mV/decade로 이론적인 Nernstian 감응기울기에는 못 미쳤으나 살리실레이트 이온 등 다른 음이온에 대한 선택성은 매우 우수하였다: KpotCl,NO3=1.3, KpotCl,I=2.0, KpotCl,Sal=0.8, KpotCl,SCN=2.0, KpotCl,ClO4=0.8. 또한 실리콘러버-지지체 전극막은 PVC-지지체 전국막에 비해 고체상 전극표면에 대한 접착력이 우수하므로 CWE형 고체상 전극에 도입되었을 때 향상된 전극수명을 나타내었다. 이들 고체상 전극들은 35일까지 염화이온에 대한 감응기울기나 살리실레이트 이온에 대한 감응성에 변화없이 우수하게 작동함을 알 수 있었다.

• 분석과학
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• 제9권3호
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• pp.270-278
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• 1996

5, 10, 15, 20-tetraphenyl(porphyrinato)manganase(III) chloride(Mn(TPP)Cl)를 감응성 물질로 사용하는 염화이온 선택성 전극의 감응 메카니즘을 동일한 막 조성을 갖는 optode의 가시광선 스펙트럼 변화를 관찰하여 연구하였다. 고분자막 내에서 망간포르피린의 리간드인 염화이온은 물분자와 치환되며, 시료 용액의 할로겐족 음이온들은 고분자막으로 들어와 망간포르피린에 치환된 물분자 리간드를 다시 치환함으로써, 그리고 살리실산과 같은 지용성 음이온들은 포르피린 주변의 염화이온들과 이온 교환을 함으로써 감응전위를 발생하는 것으로 보인다. 또한 각 음이온들에 대한 선택성을 결정하는 중요한 요소는 망간포르피린-음이온 리간드의 결합상수와 음이온의 수화엔탈피의 균형에 의하여 결정되는 것임을 확인할 수 있었다.