• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.75-75
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• 1995

Succinic semialdehyde reductase, one of key enzyme of GABA shunt in CNS, is inactivated by o-phthalaldehyde, The inactivation followed pseudo first-order kinetics, and the second-order rate constant for the inactivation process was 28 M$\^$-1/s$\^$-1/ at pH 7.4 and 25$^{\circ}C$. The absorption spectrum(λ$\_$max/=377nm), fluorescence exitation(λ$\_$max/=340nm) and fluorescence emission spectra (λ$\_$max/=409nm) were consistent with the formation of an isoindole derivative in the catalytic site between a cysteine and a lysine residues about 3${\AA}$ apart. The substrate, succinic semialdehyde, did not protect the enzymatic activity against inactivation, whereas the coenzyme, NADPH, protected against o-phthalaldehyde induced inactivation of the enzyme. About 1 isoindole group per moi of the enzyme was formed following complete loss of the enzymatic activity. These results suggest that the amino acid residues of the enzyme participating in reaction with o-phthalaldehyde more likely residues at or near the coenzyme binding site.

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.1973-1975
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• 2010

The electronic and adsorption structure of o-phthalaldehyde (OPA) on the H-Si(100) surface was investigated by using Near Edge X-ray Fine Structure (NEXAFS) and high resolution photoemission spectroscopy (HRPES). We confirmed that the OPA grown on the H-Si(100) surface showed good dependency with about 60 degree tilting angle using NEXAFS and a single O 1s peak by using HRPES. Hydrogen atom passivated on the Si(100) surface was found to be a seed for making one dimensional organic line that uses a chain reaction as the H-Si(100) surface was compared with the hydrogen free Si(100) surface.

• BMB Reports
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• 제28권2호
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• pp.112-117
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• 1995

Succinic semialdehyde reductase was inactivated by o-phthalaldehyde. The inactivation followed pseudo-first order kinetics, and the second-order rate constant for the inactivation process was 28 $M^{-1}s^{-1}$ at pH 7.4 and $25^{\circ}C$. The absorption spectrum ($\lambda_{max}$ 337 nm) and fluorescence excitation ($\lambda_{max}$ 340 nm) and fluorescence emission spectra ($\lambda_{max}$ 409 nm) were consistent with the formation of an isoindole derivative in the catalytic site between a cysteine and a lysine residue approximately about 3 $\AA$ apart. The substrate, succinic semialdehyde, did not protect enzymatic activity against inactivation, whereas the coenzyme NADPH protected against o-phthaladehyde induced inactivation of the enzyme. About 1 isoindole group per mol of the enzyme was formed following complete loss of enzymatic activity. These results suggest that the amino acid residues of the enzyme participating in a reaction with o-phthalaldehyde are cysteinyl and lysyl residues at or near the NADPH binding site.

• 분석과학
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• 제36권5호
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• pp.250-257
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• 2023

The development of a spectrofluorimetric method for the determination of trimethoprim according to the reaction between O-phthalaldehyde (OPA) in highly alkaline media, and 2-mercaptoethanol (2ME) and this reaction gives fluorescent product measured at (458) nm when excited at (342) nm. The optimization of the analytical parameters that influence intensity was investigated. The intensity of fluorescence of the formed product was linearly related to the concentration of trimethoprim in the (100-1200) ng mL^-1 range. The limit of detection and limit of quantification were estimated to be (22.54) ng mL^-1 and (75.15) ng mL^-1 respectively. The utility of the proposed methods was successfully verified by analysis of trimethoprim in pure and real pharmaceutical preparations with high accuracy, the recovery percentages Re%, were found to be (100.5) % and (99.76) % for pure drug and pharmaceutical preparations respectively.

• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of International Convention of the Pharmaceutical Society of Korea
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• pp.287.1-287.1
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• 2001

• 분석과학
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• 제8권3호
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• pp.229-236
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• 1995

생체시료에 존재하는 유리 아미노산의 분석을 위하여 pH 7.2의 완충용액 조건하에서 Amino Quant $C_{18}$ 컬럼에 diode array detector(DAD) 검출기가 부착된 HPLC에 의한 다단계 기울기 용리법이 사용되었다. 한국인 정신분열증 환자와 정상 한국인의 혈장시료내의 유리 아미노산은 3-mercaptopropionic acid 존재하에서 o-phthalaldehyde와 유도체 반응을 시켰다. 내부표준법에 의한 생체시료에서의 아미노산의 정량분석은 상대표준편차가 2~6%로서 재현성 있는 결과를 보여 주었다. 또한 한국인의 생체시료 중 아미노산의 함량은 외국인의 것과는 다른 결과를 얻었으며 정상인과 비정상인의 평균 tyrosine량은 큰 차이가 있었다.

• 분석과학
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• 제9권1호
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• pp.52-61
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• 1996

식품 중의 몇몇 유리 D-아미노산이 column switching method에 의해 검출되었다. D-아미노산과 L-아미노산의 총량의 정량은 $C_{18}$ 컬럼을 사용한 비키랄 분리에 근거한다. L-아미노산에 대한 D-아미노산의 수준은 o-phthalaldehyde로 유도체화된 아미노산의 postcolumn reaction detection을 포함하는 column switching system에 의해 정량되었다. Postcolumn detection system의 키랄 분리는 chiral crown ether 컬럼에 의해 실행되었다. 이 system은 간장과 발효된 콩, 그리고 콩 같은 식품 중에 있는 D-아미노산의 정량에 적용된다. 이 achiral/chiral coupled-column system하에서는 시료 전처리과정이 중요함을 알게 되었다. Phenylalanine은 시판용 간장 속에 242ppm, 재래식 간장 속에는 102ppm, 발효된 콩에는 1g당 8.34mg, 콩에는 1g당 2.87mg이 함유된 것으로 밝혀졌다. D-phenylalanine은 시판용 간장 속에는 0.67%, 재래식 간장에는 0.34%, 발효된 콩에는 1.81% 미만, 콩에는 2.82% 미만이 검출되었다.

• Applied Biological Chemistry
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• 제39권1호
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• pp.84-88
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• 1996

벼의 생육 단계별 brassinolide의 검정을 위하여 HPLC 형광분석법을 개발하였다. 형광분석에 민감한 1-cyanoisoindole-2-m-phenylboronic acid를 o-phthalaldehyde와 m-phenylbornic acid 및 KCN과 반응시켜 합성하여 brassinolide의 1, 2-diol과 유도체화 시켰다. Brassinolide $1\;{\mu}g$에 대한 1-cyanoisoindole-2-m-phenylboronic acid의 brassinolide boronate의 형성정도는 $20\;{\mu}g$에서 90% 이상의 유도체화를 보였고 형광검출법에 의한 brassinolide의 검출한계는 0.16 ng이었다. 벼의 생육단계별 brassinolide는 분얼기 및 신장기에서는 검출이 되지 않았으며 유수형성기에는 $0.8\;{\mu}g$(생체 10g)이 그리고 출수개화기에는 $0.2\;{\mu}g$(생체 10g)이 검출되었다.

• 대한화학회지
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• 제29권5호
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• pp.543-551
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• 1985

$p^-$, $m^-$, o-phthalaldehyde 및 5,5'-methylene-bis-salicyl aldehyde (PPTA, MPTA, OPTA, MBSA)와 5,5'-methylene-bis-salicylic dihydrazide, terephthalic dihydrazide 및 sebacic dihydrazide(MBSDH, TDH 및 SDH)등의 디히드라지드 화합물을 DMF-$CH_3COOH$ 혼합용액 중에서 축합반응으로 몇가지 새로운 폴리히드라존을 합성하였다. 합성한 폴리히드라존과 그의 금속킬레이트의 용해성, 흡수스펙트라 및 열적성질에 대하여 검토하였다. OPTA와 MBSDH의 반응으로 얻어진 폴리히드라존을 제외한 폴리히드라존과 그의 금속킬레이트는 일반적으로 보통 유기용매에 불응성이었다. 폴리히드라존의 중량열분석 결과 250-350$^{\circ}$C 사이에서 10%의 중량감소가 일어났고 500$^{\circ}$C고 500 폴리히드라존의 중량열분석 결과 250~350$^{\circ}$C 사이에서 10%의 중량감소가 일어났고 500$^{\circ}$C에서 32.5~63.5% 범위의 잔유중량을 나타내었다. 합성한 폴리히드라존 중에서 PPTA-MBSDH(IIa)및 MBSA-MBSDH(IIIa)가 열분해온도가 비교적 높았으며 IIa의 금속킬레이트에 있어서는 Zn(II)-IIa>Ni(II)-IIa>Co(II)-IIa>Cu(II)-IIa의 순서로 열분해온도가 저하되었다.

• Molecular & Cellular Toxicology
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• 제3권4호
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• pp.273-281
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• 2007

Ceramide is involved in cell death as a lipid mediator of stress responses. In this study, we developed an improved method of ceramide quantification based on added synthetic ceramide and thin layer chromatography (TLC) separation, and applied to biological samples. Lipids were extracted from samples spiked with N-oleoyl-D-erythro-sphingosine ($C_{17}$ ceramide) as an internal standard. Ceramide was resolved by TLC, complexed with fatty-acidfree bovine serum albumin (BSA), and deacylated by ceramidase (CDase). The released sphingosine was derivatized with o-phthalaldehyde (OPA) and measured by high performance liquid chromatography (HPLC). The limit of detection for ceramide was about 1-2 pmol and the lower limit of quantification was 5 pmol. Ceramide recovery was approximately 86-93%. Ceramide concentrations were determined in biological samples including cultured cells, mouse tissues, and mouse and human plasma. TLC separation of ceramide provides HPLC chromatogram with a clean background without any interfering peaks and the enhanced solubility of ceramide by BSAceramide complex leads to the increased deacylation of ceramide. The use of an internal standard for the determination of ceramide concentration in these samples provides an accurate and reproducible analytical method, and this method can be applicable to diverse biological samples.