• 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.

• 공업화학
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• 제30권6호
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• pp.737-741
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• 2019

본 연구에서는 스크린 프린팅 공정을 이용하여 저렴하고 유연한 칼륨 이온(K⁺) 센서를 제작하였다. 전도성 잉크의 균일한 코팅은 주사 전자 현미경 및 광학 현미경 측정에 의해 입증되었다. K⁺ 센서는 높은 감도, 빠른 응답 시간, 낮은 검출 한계를 보여주었다. 제조된 K⁺ 센서의 감도는 기계적으로 구부러진 상태에도 여전히 유지되었다. 히스테리시스 효과가 없는 우수한 반복성과 우수한 장기 안정성이 K⁺ 센서의 전기화학적 특성 분석에서 관찰되었다. 또한, K⁺ 센서는 다른 간섭 양이온이 존재하는 경우에도 정확하게 K⁺ 농도를 측정 할 수 있어 우수한 선택성을 증명하였다. 또한, 실제 스포츠 음료 샘플에서 K⁺ 농도의 성공적인 측정은 K⁺ 센서의 K⁺ 농도 값과 상용 K⁺ 미터를 비교하여 증명되었다.

• Bulletin of the Korean Chemical Society
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• 제32권8호
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• pp.2722-2726
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• 2011

Plasticized poly(vinyl chloride), PVCs, with different membrane compositions tested for use in the construction of an ion-selective sensor for the determination dibucaine. A prepared membrane with dioctyl phthalate-PVC and ion-pair of N-(1-naphthyl)ethylenediamine dihydrochloride-tetraphenyl borate had a good potential to acts as a potentiometric sensor for the analysis of dibucaine. A linear relationship was obtained between potential and logC varying between $1.0{\times}10^{-6}$ and $1.0{\times}10^{-2}$ M dibucaine with a good repeatability and reproducibility. The sensor was applied for the determination of the drug in pharmaceuticals and biological fluids such as plasma and urine samples with satisfactory results. The drug electrode has also been used to study the interaction of bovine serum albumin (BSA) with dibucaine. The saturated quantities of dibucaine binding were 13.04, 5.30 and 9.70 mol/mol in 0.01, 0.02 and 0.1% of protein, respectively.

• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2359-2364
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• 2012

Two new chemosensors, rhodamine 6G derivative bearing hydroxyethyl group (1) and rhodamine base derivative bearing 15-crown-5 group (2) were synthesized and their sensing behaviors toward various metal ions were investigated by UV/Vis and fluorescence spectroscopies. Addition of $Hg^{2+}$ ion to a $CH_3CN$ solution of 1 and 2 gave visual color changes as well as fluorescent OFF-ON observations. Selectivity and sensitivity of 1 towards $Hg^{2+}$ are excellent enough to detect micromolar level of $Hg^{2+}$ ion, even in equeous media and biological sample (HeLa cell).

• 대한화학회지
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• 제46권5호
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• pp.407-411
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• 2002

납이온과 선택적으로 상호작용하는 이온 운반물질(lead ionophore II)과 수소이온과 선택적으로 상호작용하면서 형광을 내는 변색성 이온 운반물질(ETH5294) 및 소수성의 음이온 자리를 포함하는 이온 선택성 광센서를 제조하여 형광분광법으로 수용액 중의 납이온을 정량하는 방법을 연구하였다. 시료용액의 pH,막두께 등이 형광세기에 미치는 영향을 조사하였다. $Na^+$, $K^+$, $Mn^{2+}$ 및 $Zn^{2+}$이온 등의 방해이온이 납이온의 정량에 미치는 영향을 조사하였다.본 연구에서 제작한 납이온 선택성 막을 이용하여 얻은 납이온 검정곡선의 직선범위는 5.0${\times}10^-7$M5.0${\times}10^-3$M이였고 이 범위에서의 상관계수는 -0099107이었다. 바탕용액의 상대표준편차는 3.0%였고 납이온의 검출한계는 5.0${\times}10^-9$M이었다.

• Bulletin of the Korean Chemical Society
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• 제29권7호
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• pp.1395-1398
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• 2008

• Journal of Biosystems Engineering
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• 제28권4호
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• pp.335-342
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• 2003

A simple disposable thick-film potentiometric strip has been developed and evaluated for hydroponics application. The strip consisted of low ion-selective electrodes (ISE) fabricated by screen-printing technology. The electrochemical responses of ion sensors for nitrate, ammonium, potassium, and magnesium were measured with specially designed 16-channel low voltage signal transducers. The analytical characteristics of the sensors were comparable with those of conventional ISE sensors. The thick-film sensors exhibit linear relationships over five concentration decades. The concentration of N $O_3$ - ion in standard solution can be determined by direct potentiometric measurements without any conditioning before measurements. However, measurement of $K^{+}$, N $H_4$$^{+}$, and $Mg^{2+}$ ionic concentrations in nutrient solutions seems not feasible.

• E2M - 전기 전자와 첨단 소재
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• 제9권5호
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• pp.518-525
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• 1996

본 고에서는 유리 집적광센서의 제작에 적합한 유리재료들의 종류와 특성을 설명하였으며, 이들 유리의 종류에 맞도록 개발되어진 제작기술 중에서 이온교환(Ion exchange)방법과 silica-on-silicon(SOS)방법을 소개하였다. 그리고 이러한 공정기술을 이용하여 제작되어진 유리 집적광센서 중에서 물체의 거리를 측정하기 위한 마이클슨 간섭계(michelson interferometer)와 물질의 농도를 측정하기 위한 화학센서(chemical sensor)들을 소개하였다.

• Bulletin of the Korean Chemical Society
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• 제27권6호
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• pp.899-902
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• 2006

The complexation of N,N'-4,5-(ethylenedioxy)benzenebis(salicylideneimine), (salphen$H_2$) with uranyl ion was studied in acetonitrile solution spectrophtometrically, and the formation constant of the resulting 1 : 1 complex was evaluated. The salphen$H_2$ ligand was used as an ionophore in plasticized poly(vinyl chloride) (PVC) matrix membrane sensor for uranyl ion. The prepared sensors exhibited a near Nernstian response, 28.0-30.9 mV/decade for uranyl ion over the concentration range $1.0\;{\times}\;10^{-2}$ to $1.0\;{\times}\;10^{-6}$M with a limit of detection of $3.2\;{\times}\;10^{-7}$ M. The proposed electrode could be used at a working pH range of 1.5 - 4.0.

• Bulletin of the Korean Chemical Society
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• 제25권2호
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• pp.177-181
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• 2004

A PVC membrane electrode for silver ion based on a new cone shaped calix[4]arene (CASCA) as membrane carrier was prepared. The electrode exhibits a Nernstian response for $Ag^+$ over a wide concentration range ($1.0{\times}10^{-1}-8.0{\times}10^{-6}$M) with a slope of 58.2 {\pm}$ 0.5 mV per decade. The limit of detection of the sensor is $5.0{\times}10^{-6}$M. The sensor has a very fast response time (~5 s) in the concentration range of ${\leq}=1.0{\times}10^{-3}$ M, and a useful working pH range of 4.0-9.5. The proposed sensor displays excellent discriminating ability toward $Ag^+$ ion with respect to common alkali, alkaline earth, transition and heavy metal ions. It was used as an indicator electrode in potentiometric titration of $Ag^+$ with EDTA and in direct determination of silver ion in wastewater of silver electroplating.