• Title/Summary/Keyword: GC/MS

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Determination of the PDE-5 Inhibitors and Their Analogues by GC-MS and TMS Derivatization

  • Pyo, Jae-Sung;Lee, Hee-Sang;Park, Yu-Jin;Jo, Ji-Yeong;Park, Yong-Hoon;Choe, Sang-Gil;Lee, Mi-Young;Lee, Jae-Sin
    • Mass Spectrometry Letters
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    • v.3 no.1
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    • pp.15-17
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    • 2012
  • Eighteen of the PDE-5 inhibitors and their analogues were analyzed using GC-EI-MS. Fourteen of them could be identified by simple GC-MS method without derivatization, but hydroxyhongdenafil, hydroxyvardenafil, xanthoanthrafil and mirodenafil could not be identified without derivatization for the high polarity due to the presence of hydroxyl groups. N,O-bis(trimethylsilyl) trifluoroacetamide (BSTFA) and N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide (MTBSTFA), widely used trimethylsilyl (TMS) derivatizing reagents, were used to improve the sensitivity of the hydroxylated analogues. And the analytes could be identified by GC-MS after the derivatization.

Gas Chromatography-High Resolution Tandem Mass Spectrometry Using a GC-APPI-LIT Orbitrap for Complex Volatile Compounds Analysis

  • Lee, Young-Jin;Smith, Erica A.;Jun, Ji-Hyun
    • Mass Spectrometry Letters
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    • v.3 no.2
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    • pp.29-38
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    • 2012
  • A new approach of volatile compounds analysis is proposed using a linear ion trap Orbitrap mass spectrometer coupled with gas chromatography through an atmospheric pressure photoionization interface. In the proposed GC-HRMS/MS approach, direct chemical composition analysis is made for the precursor ions in high resolution MS spectra and the structural identifications were made through the database search of high quality MS/MS spectra. Successful analysis of a complex perfume sample was demonstrated and compared with GC-EI-Q and GC-EI-TOF. The current approach is complementary to conventional GC-EI-MS analysis and can identify low abundance co-eluting compounds. Toluene co-sprayed as a dopant through API probe significantly enhanced ionization of certain compounds and reduced oxidation during the ionization.

Analysis of Phenolic Acids in Tobacco Leaf by GC/MS (GC/MS에 의한 잎담배중 Phenolic Acid의 분석)

  • 박진우
    • YAKHAK HOEJI
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    • v.26 no.2
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    • pp.129-132
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    • 1982
  • A GC/MS method was developed to analyze phenolic acid extract from tobacco leaf. Extracted acids were converted to their methyl esters by refluxing with 3M hydrogen chloride in methanol, and the esters were reacted with his (trimethylsilyl) trifluoroacetamide plus 10% trimethylchlorosilane to silylate the phenolic groups. Derivatives of standard salicylic, p-hydroxybenzoic, vanillic, gentisic, p-coumaric, syringic, ferulic, and sinapic acids prepared by this procedure were analyzed by GC/MS on $20m{\times}0.2mm$ column of SE-54 glass capillary. GC/MS analysis of the extract from tobacco leaf revealed the presence of salicylic, p-hydtoxybenzoic, vanillic, gentisic, protocatechuic, p-coumaric, syringic, gallic, ferulic, caffeic, sinapic, and quinic acids, respectively. The quantitative analysis of these phenolic acids were achieved by using multiple ion selection technique.

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Identification of Brassinosteroids in Immature seeds of Zea mays by GC-MS analysis (GC-MS에 의한 옥수수 미숙종자의 Brassinosteroid 동정)

  • Kim, Seon-Jae;Yokota, T.;Park, Keun-Hyung
    • Applied Biological Chemistry
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    • v.38 no.2
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    • pp.179-183
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    • 1995
  • The brassinosteroid-like active principles from immature seeds of Zea mays were purified and identified as castasterone, teasterone, 28-norcastasterone and 6-deoxocastasterone by GC-MS analysis. Our work is probably the first report that showed the presence of brassinosteroids in Zea mays seeds.

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Analysis of Phenolic Components in Korean Red Ginseng by GC/MS (홍삼 페놀성 성분의 GC/MS분석)

  • Wee, Jae-Joon;Heo, Jeong-Nam;Kim, Man-Wook
    • Journal of Ginseng Research
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    • v.20 no.3
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    • pp.284-290
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    • 1996
  • To Identify phenolic components known to exist in Korean ginseng (Panax ginseng C.A. Meyer) by GC/MS, three derivatization methods were employed for their analyses. First, phenolic components in ether soluble acidic fraction prepared from Korean red ginseng powder were taimethylsilylated. Secondly, phenolic acids in the same fraction were esterified with diazomethane followed by trlmethylsilylation. Thirdly, acidic components in ginseng powder were extracted and esterified concurrently by methanolic sulfuric acid, followed by fractionation of phenolic components with Silica Sep-Paka and trimethylsilylatlon. All phenolic components found in ginseng except gen tisic acid were identified by retention times and mass spectrums of standards. Besides, 5 phenolic components including salicyl alcohol and 1-H-indole-2-carboxylic acid were first identified from Korea an red ginseng by GC/MS.

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Simultaneous Determination of Preservatives in Food by GC/MS (Gas Chromatography/Mass Spectrometry를 이용한 식품보존료의 동시분석방법 연구)

  • 김승기;노동석
    • Journal of Food Hygiene and Safety
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    • v.14 no.2
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    • pp.140-145
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    • 1999
  • Analytical method for preservatives in food was developed using gas chromatography/mass spectrometry (GC/MS). Propionic acid, sorbic acid, benzoic acid, ethyl salicylate, ethyl p-hydroxy benzoate, iso-propyl p-hydroxy benzoate, n-propyl p-hydroxy benzoate, iso-butyl p-hydroxy benzoate, n-butyl p-hydroxy benzoate, p-hydroxy benzoic acid and dehydro acetic acid were extracted from cooling beverage with diethyl ether. The polar hydroxyl and carboxyl groups of food preservatives were derivatized with N-methyl-N-tert-butyldimethylisilyl-trifluoroscetamide (MTBSTFA) to form the corresponding tert-bytyldimethyl-silylated derivatives, and submitted to GC/MS analysis. The mass spectra of the derivatives were investigated for the selection of monitoring ions for multi-residue analysis of 11 preservatives by GC/MS. The macro program was also developed for the qualitative analysis of these preservatives in food.

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Determination of more than 500 Pesticide Residues in Hen Eggs by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) and Gas Chromatography-Tandem Mass Spectrometry (GC/MS/MS)

  • Golge, Ozgur;Liman, Turan;Kabak, Bulent
    • Food Science of Animal Resources
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    • v.41 no.5
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    • pp.816-825
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    • 2021
  • This study aims to validate a fast method of simultaneous analysis of 365 LCamenable and 142 GC-amenable pesticides in hen eggs by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS), respectively, operating in multiple reaction monitoring (MRM) acquisition modes. The sample preparation was based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction. Key method performance parameters investigated were specificity, linearity, limit of quantification (LOQ), accuracy, precision and measurement uncertainty. The method was validated at two spiking levels (10 and 50 ㎍/kg), and good recoveries (70%-120%) and relative standard deviations (RSDs) (≤20) were achieved for 92.9% of LC-amenable and 86.6% of GC-amenable pesticide residues. The LOQs were ≤10 ㎍/kg for 94.2% of LC-amenable and 92.3% of GC-amenable pesticides. The validated method was further applied to 100 egg samples from caged hens, and none of the pesticides was quantified.

Flavor Components of Poncirus trifoliata (탱자(Poncirus trifoliata)의 향기성분 분석에 관한 연구)

  • Oh, Chang-Hwan;Kim, Jung-Han;Kim, Kyoung-Rae;Ahn, Hey-Joon
    • Korean Journal of Food Science and Technology
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    • v.21 no.6
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    • pp.749-754
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    • 1989
  • The essential oil was prepared by a gas co-distillation method from flavedo of Poncirus trifoliata and was analyzed by GC/ retention index (RI) and GC/MS. The essential oil prepared by a gas co-distillation gave a whole fragrance of Poncirus trifoliata. The identification of the flavor components was performed by multi-dimensional analysis using GC/RI and GC/MS. GC/RI and GC/MS were complementary to each other. In applying GC/RI for identification, it was more effective when two columns of different polarities were used. Thirty volatile flavor constituents were identified in Poncirus trifoliata. Limonene, myrcene, ${\beta}-caryophyllene,\;trans-{\beta}-ocimene$, ${\beta}-pinene$, 3-thujene and 7-geranyloxycoumarin were the major constituents and cis-3-hexenyl acetate, n-hexyl acetate, 2-methyl acetophenone, elixene and elemicine had not been reported earlier as citrus components.

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Analysis of Synthetic Fragrances (SFs) in Water Using Stir Bar Sorptive Extraction (SBSE) and GC-MS/MS (교반막대 추출법과 GC-MS/MS를 이용한 수중의 합성 향물질류 분석)

  • Seo, Chang-Dong;Son, Hee-Jong;Yoom, Hoon-Sik;Choi, Jin-Taek;Ryu, Dong-Choon;Kwon, Ki-Won;Jang, Seung-Ho
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.6
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    • pp.387-395
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    • 2014
  • A highly sensitive analytical method based on stir bar sorptive extraction (SBSE) technique and gas chromatography/tandem mass spectrometry (GC-MS/MS) has been developed, allowing the simultaneous multi-analyte determination of 11 synthetic fragrances (SFs) in water samples. The stir bar coated with polydimethylsiloxane (PDMS) was added to 40 mL of water sample at pH 3 and stirred at 1,100 rpm for 120 min. Other SBSE parameters (salt effect and presence of organic solvent) were optimised. The method shows good linearity (coefficients > 0.990) and reproducibility (RSD < 10.9%). The extraction efficiencies were above 83% for all the compounds. The limits of detections (LOD) and limits of quantification (LOQ) were 2.1~4.1 ng/L and 6.6~12.9 ng/L, respectively. The developed method offers the ability to detect 11 SFs at ultra-low concentration levels with only 40 mL of sample volume. Matrix effects in tap water, river water, wastewater treatment plant (WWTP) final effluent water and seawater were investigated and it was shown that the method is suitable for the analysis of trace level of 11 SFs. The method developed in the present study has the advantage of being rapid, simple, high-sensitive and both user and environmentally friendly.

Determination of Additives Content in Aviation Turbine Fuel Using Multi-dimensional GC-MS (Multi-dimensional GC-MS를 이용한 항공터빈유의 첨가제 분석)

  • Youn, Ju Min;Jang, Yoon Mi;Yim, Eui Soon;Kim, Seong Lyong;Kang, Yong
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.4
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    • pp.1260-1268
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    • 2018
  • To improve fuel performance and specific characteristics of long storage and moving through fuel systems additives should be added in kerosene type aviation turbine fuel (AVTUR) such as antioxidant, fuel system icing inhibitor (FSII), electric conductivity improvers and so on. The dosage of additives has to be analyzed qualitatively and quantitatively due to inspect the quality of abnormal fuel and distinguish other petroleum products. Multi-dimensional GC-MS (MDGC-MS) with Deans switching technique are applied the determination of antioxidant and FSII, which are added with AVTUR containing complex mixture of hydrocarbons. Antioxidant and FSII in the range of 2.5-20 mg/L was quantitatively and qualitatively analyzed using MDGC-MS and the detection limit was about twice as low as that of the 1-dimensional GC-MS results. The method in this study has been higher peak resolution compared with GC-MS and could be simultaneously analyzed different two additives without sample pre-treatment.