• 제목/요약/키워드: Potentiometric determination

검색결과 51건 처리시간 0.022초

Improved Thiocyanate-Selective Electrode Based on Tetra(trimethylphenyl)-porphyrinato Manganese(III) Chloride: The Electronic and pH Effects

  • Seo, Hyung-Ran;Lee, Hyo-Kyoung;Jeon, Seung-Won
    • 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 $SCN^-$.

구리수은막 전극에을 사용한 이소니아자이드의 전위차 역적정 (Potentiometric Back Titration of Isoniazid in Pharmaceutical Dosage Forms Using Copper Based Mercury Film Electrode)

  • Gajendiran, M.;Nazer, M.M. Abdul Kamal
    • 대한화학회지
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    • 제55권4호
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    • pp.620-625
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    • 2011
  • 구리수은막 전극(CBMFE)으로 전위차 역적정함으로써 이소니아자이드(INH)를 정량하는 간단하고 빠른 방법이다. 순수한 형태와 투약형태에 대해서 1.0-10.0 mg 범위에서 정량 할 수 있도록 적정조건을 설정하였다. 방법의 정밀도와 정확도는 통계적인 방법으로 평가되었으며, 정제와 시럽속에 함유된 INH 정량법은 F-시험과 t-시험을 통하여 영국약전(BP) 방법과 비교하였다.

PVC 액체막 전극을 이용한 Norfloxacin의 정량 (A PVC Liquid Membrane Electrodes for the Determination of Norfloxacin)

  • 김동오;남수자;문현숙;정문모;허문회;김대병;안문규
    • 약학회지
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    • 제44권5호
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    • pp.406-410
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    • 2000
  • The present method is to describe a potentiometric norfloxacin electrode system characterized by a membrane, based on the use of norfloxacin (NF) complex with ion-association reagents. These complexes were dissolved in DMSO, DMF acetonitrile or acetone and dispersed in plasticized poly(vinyl chloride) matrix. The picric acid complex electrode exhibited near-Nernstian response for NF in acetate buffer solution (pH 4.0) with a slope of 53.03 mV/decade. And linear response over the range of 10$^{-5}$ to 10$^{-3}$M solution of NE. The ingredients in tablet, capsule and biological important organic acids were not interfere.

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이온교환체로서 금속-디-2-피리딜케톤옥심-산성의약품 3원 착물을 이용한 산성의약품의 정량 (Determination of Acidic Drug with ISEs Using Ternary Complex of Metal-di-2-pyridyl Ketone Oxime-acidic Drug as Ion-Exchanger)

  • 안문규;오원정;이언경;이순영;이재윤;정문모;허문회
    • 약학회지
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    • 제46권5호
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    • pp.320-323
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    • 2002
  • A method for the determination of acidic drug, mefenamic acid and ibuprofen with ion-selective electrode(ISE) using Fe(II)-di-2-pyridyl ketone oxime complex as a counter ion were developed. Benzyl-2-nitrophenyl ether(BNPE) plasticized membrane was more selective and sensitive than the other tested membranes. The acidic drug selective electrode exhibits a linear response for 10$^{-2}$ M 510$^{-5}$ M of acidic drugs, mefenamic acid and ibuprofen with a slope of -55.9 and -56.3 mV/dec. in borate buffer solution (pH 8.9). Potentiometric selectivity measurements revealed negligible interferences from aromatic and aliphatic carboxylic acid salts. The electrodes were found to be useful for the direct determination of mefenamic acid and ibuprofen in pharmaceutical preparations.

전위차법을 이용한 경화 콘크리트 및 콘크리트재료의 염화물 측정기술 개발 (Study for the Determination of chloride ion in hardened concrete using Potentiometic Methods)

  • 이경문;윤인준;서인호
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.578-581
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    • 2006
  • This study was performed to develop acid-soluble extraction solution and water-soluble extraction solution for hardened concrete. By use of this potentiometric method one can determinate chloride ion concentration in hardened concrete without pre-treatment and it can be used on-site.

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A Solid-Contact Indium(III) Sensor based on a Thiosulfinate Ionophore Derived from Omeprazole

  • Abbas, Mohammad Nooredeen;Amer, Hend Samy
    • Bulletin of the Korean Chemical Society
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    • 제34권4호
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    • pp.1153-1159
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    • 2013
  • A novel solid-contact indium(III)-selective sensor based on bis-(1H-benzimidazole-5-methoxy-2-[(4-methoxy-3, 5-dimethyl-1-pyridinyl) 2-methyl]) thiosulfinate, known as an omeprazole dimer (OD) and a neutral ionophore, was constructed, and its performance characteristics were evaluated. The sensor was prepared by applying a membrane cocktail containing the ionophore to a graphite rod pre-coated with polyethylene dioxythiophene (PEDOT) conducting polymer as the ion-to-electron transducer. The membrane contained 3.6% OD, 2.3% oleic acid (OA) and 62% dioctyl phthalate (DOP) as the solvent mediator in PVC and produced a good potentiometric response to indium(III) ions with a Nernstian slope of 19.09 mV/decade. The constructed sensor possessed a linear concentration range from $3{\times}10^{-7}$ to $1{\times}10^{-2}$ M and a lower detection limit (LDL) of $1{\times}10^{-7}$ M indium(III) over a pH range of 4.0-7.0. It also displayed a fast response time and good selectivity for indium(III) over several other ions. The sensor can be used for longer than three months without any considerable divergence in potential. The sensor was utilized for direct and flow injection potentiometric (FIP) determination of indium(III) in alloys. The parameters that control the flow injection method were optimized. Indium(III) was quantitatively recovered, and the results agreed with those obtained using atomic absorption spectrophotometry, as confirmed by the f and t values. The sensor was also utilized as an indicator electrode for the potentiometric titration of fluoride in the presence of chloride, bromide, iodide and thiocyanate ions using indium(III) nitrate as the titrant.

Novel Copper(Ⅱ)-Selective Senor Based on a New Hexadentates Schiff's Base

  • Ganjali, Mohammad Reza;Emami, Mehdi;Salavati Niasari, Masoud
    • Bulletin of the Korean Chemical Society
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    • 제23권10호
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    • pp.1394-1398
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    • 2002
  • A novel copper(II) membrane electrode based on diphenylisocyanate bis(acetylacetone) ethylenediimine (DIBAE), as a new hexadentates Schiff's base was prepared. The electrode exhibited a Nernstian response for Cu$^{2+}$ ions over a wide concentration range (1.0 ${\times}$ 10$^{-1}$ to 1.0 ${\times}$ l0$^{-6}$ M) with a limit of detection of 6.0 ${\times}$ 10$^{-7}$ M (39 ppb). The sensor shows a fast response time (15s) and the membrane can be used for more than 4 months without observing any major deviation. The electrode revealed very good selectivity with respect to many cations including alkali, alkaline earth, transition and heavy metal ions. The proposed sensor could be used in a pH range of 3.0-7.5. It was applied to the direct potentiometric determination of copper in black tea, and in wastewater of copper electroplating samples. The electrode was also used in potentiometric titration of the copper(II) ion with EDTA.

Synthesis of a New Hexadendates Schiff's Base and Its Application in the Fabrication of a Highly Selective Mercury(II) Sensor

  • Ganjali, M.R.;Norouzi, P.;Alizadeh, T.;Salavati-Niasari, M.
    • Bulletin of the Korean Chemical Society
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    • 제28권1호
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    • pp.68-72
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    • 2007
  • A new PVC membrane potentiometric sensor that is highly selective to Hg2+ ions was prepared, using bis(2-hydroxybenzophenone) butane-2,3-dihydrazone (HBBD) as an excellent hexadendates neutral carrier. The sensor works satisfactorily in the concentration range of 1.0 × 10-6 to 1.0 × 10-1 mol L-1 (detection limit 4 × 10-7 mol L-1) with a Nernstian slope of 29.7 mV per decade. This electrode showed a fast response time (~8 s) and was used for at least 12 weeks without any divergence. The sensor exhibits good Hg2+ selectivity for a broad range of common alkali, alkaline earth, transition and heavy metal ions (lithium, sodium, potassium, magnesium, calcium, copper, nickel, cobalt, zinc, cadmium, lead and lanthanum). The electrode response is pH independent in the range of 1.5-4.0. Furthermore, the developed sensor was successfully used as an indicator electrode in the potentiometric titration of mercury ions with potassium iodide and the direct determination of mercury in some binary and ternary mixtures.

A New Fe (III)-Selective Membrane Electrode Based on Fe (II) Phthalocyanine

  • Ozer, Tugba;Isildak, Ibrahim
    • Journal of Electrochemical Science and Technology
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    • 제10권3호
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    • pp.321-328
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    • 2019
  • A new miniaturized all solid-state contact Fe (III)-selective PVC membrane electrode based on Fe (II) phthalocyanine as a neutral carrier was described. The effects of the membrane composition and foreign ions on the electrode performance was investigated. The best performance was obtained with a membrane containing 32% poly (vinyl chloride), 64% dioctylsebacate, 3% Fe (II) phthalocyanine, and 1% potassium tetrakis (p-chlorophenyl) borate. The electrode showed near Nernstian response of $26.04{\pm}0.95mV/decade$ over the wide linear concentration range $1.0{\times}10^{-6}$ to $1.0{\times}10^{-1}M$, and a very low limit of detection $1.8{\pm}0.5{\times}10^{-7}M$. The potentiometric response of the developed electrode was independent at pH 3.5-5.7. The lifetime of the electrode was approximately 3 months and the response time was very short (< 7 s). It exhibited excellent selectivity towards Fe (III) over various cations. The miniaturized all solid-state contact Fe (III)-selective membrane electrode was successfully applied as an indicator electrode for the potentiometric titration of $1.0{\times}10^{-3}M$ Fe (III) ions with a $1.0{\times}10^{-2}M$ EDTA and the direct determination of Fe (III) ions in real water samples.