• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.3114-3114
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• 2001

During the last years phytochemistry and phytopharmaceutical applications have developed rapidly and so there exists a high demand for faster and more efficient analysis techniques. Therefore we have established a near infrared transflectance spectroscopy (NIRS) method that allows a qualitative and quantitative determination of new polyphenolic pharmacological active leading compounds within a few seconds. As the NIR spectrometer has to be calibrated the compound of interest has at first to be characterized by using one or other a combination of chromatographic or electrophoretic separation techniques such as thin layer chromatography (TLC), high performance liquid chromatography (HPLC), capillary electrophoresis (CE), gas chromatography (GC) and capillary electrochromatography (CEC). Both structural elucidation and quantitative analysis of the phenolic compound is possible by direct coupling of the mentioned separation methods with a mass spectrometer (GC-MS, LC-MS/MS, CE-MS, CEC-MS) and a NMR spectrometer (LC-NMR). Furthermore the compound has to be isolated (NPLC, MPLC, prep. TLC, prep. HPLC) and its structure elucidated by spectroscopic techniques (UV, IR, HR-MS, NMR) and chemical synthesis. After that HPLC can be used to provide the reference data for the calibration step of the near infrared spectrometer. The NIRS calibration step is time consuming, which is compensated by short analysis times. After validation of the established NIRS method it is possible to determine the polyphenolic compound within seconds which allows to raise the efficiency in quality control and to reduce costs especially in the phytopharmaceutical industry.

• 분석과학
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• 제16권6호
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• pp.488-498
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• 2003

LC/MS/MS를 이용하여 발기부전 (impotence) 치료제인 sildenafil 및 유사체인 homosildenafil, vardenafil, tadalafil을 분석하는 방법을 확립하였다. 이온화 방법으로는 electrospray ionization (ESI)와 atmospheric pressure chemical ionization (APCI) 방법을 사용하였으며 최대 감도와 재현성을 나타내는 조건을 찾기 위하여 여러 가지 파라미터를 변화시켜서 비교하였다. MRM (multiple reaction monitoring)을 위한 적절한 생성이온 (product ion)을 얻기 위하여 ESI 방법에서는 capillary voltage, cone voltage, extractor, entrance, RF lens를 변화시켰으나 전구이온 (precursor ion)을 제외한 뚜렸한 토막이온 (fragment ion)은 생성되지 않았다. 한편, APCI 방법의 경우 entrance, collision energy, exit, corona voltage, cone voltage, extractor, RF lens, cone gas, desolvation gas를 변화시켰을 때 다른 파라미터들의 변화에 따른 전구이온을 제외한 product ion 생성 패턴의 변화는 감지되지 않고 단지 RF lens 조건의 변화에서 precursor ion을 비롯한 토막이온들의 생성과 더불어 S/N의 증가로 인한 검출 한계의 향상이 나타났다. HPLC에서의 최적 분리 조건과 질량 분석기에서 최대 감도를 나타내는 이동상 조건도 조사되었는데 10 mM ammonium formate (pH 4.8):acetonitrile=70:30 의 등용매 용리조건이 좋은 감도를 나타내었으며, 최적의 방법인 ESI-MRM 방법에서 검출한계 (S/N>5)는 sildenafil은 $0.10{\mu}g/mL$, homosildenafil은 $0.025{\mu}g/mL$, vardenafil은 $0.025{\mu}g/mL$ 그리고 tadalafil은 $0.25{\mu}g/mL$이었다.

• Mass Spectrometry Letters
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• 제3권1호
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• pp.10-14
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• 2012

Artificially oxidized cysteine residues in peroxiredoxin 6 (Prx6) were detected by electrospray interface capillary liquid chromatography-linear ion trap mass spectrometry after the preparation of two-dimensional gel electrophoresis (2D-GE). We used Prx6 as a model protein because it possesses only two cysteine residues at the 47th and 91st positions. The spot of Prx6 on 2D-GE undergoes a basic (isoelectric point, pI 6.6) to acidic (pI 6.2) shift by exposure to peroxide due to selective overoxidation of the active-site cysteine Cys-47 but not of Cys-91. However, we detected a tryptic peptide containing cysteine sulfonic acid at the 47th position from the basic spot and a peptide containing both oxidized Cys-47 and oxidized Cys-91 from the acidic spot of Prx6 after the separation by 2D-GE. We prepared two types of oxidized Prx6s: carrying oxidized Cys-47 (single oxidized Prx6), and other carrying both oxidized Cys-47 and Cys-91 (double oxidized Prx6). Using these oxidized Prx6s, the single oxidized Prx6 and double oxidized Prx6 migrated to pIs at 6.2 and 5.9, respectively. These results suggest that oxidized Cys-47 from the basic spot and oxidized Cys-91 from the acidic spot are generated by artificial oxidation during sample handling processes after isoelectric focusing of 2D-GE. Therefore, it is important to make sure of the origin of cysteine oxidation, if it is physiological or artificial, when an oxidized cysteine residue(s) is identified.

• 한국식품조리과학회지
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• 제6권4호통권13호
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• pp.27-32
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• 1990

Triglyceride는 구성지방산의 종류에 따라 분자종이 다양하게 존재하여 식품의 가공, 저장중에 있어서 유지의 물성변화 및 산화특성을 효과적으로 규명하기 위해서는 구성 triglyceride 분자종의 상세한 해석이 요구된다고 하겠다. 율무 지질의 triglyceride를 reverse phase HPLC UV detector 210nm에서 분석한 결과 6개의 peak로 분획되었다. 각 획분을 GC로 acycl 탄소수별로 분획하고, 다시 DEGS column을 이용하여 fatty acid 조성을 분석하였다. 이 세가지 결과로부터 triglyceride 조성을 산정한 결과 11개의 TG 조성을 추산하였으며, 그 중 주요 triglyceride로는 C18 : 1 C18 : 2 C18 : 2(OLL)이 38.2%, C16 : 0 C18 : 2 C18 : 3(PLLn)이 15.7%, C18 : 1 C18 : 1 C18 : 2(OOL)이 12.6%였다. 한편 capillary GC와 GC-MS로 같은 시료를 분석하여 분자종을 확인하는 작업을 계속하고 있으며 위의 결과와 비교하여 다음에 보고하고자 한다.