• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.458-461
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• 2003

Solid-phase microextraction (SPME) and gas chromatography/headspace techniques(HS) and flame ionization detection (GC/FID) have been combined for determination of very polar compounds in water, including the widely used gasoline oxygenates and by-products. A relatively simple extraction method using a CAR/PDMS(75${\mu}{\textrm}{m}$) SPME fiber was optimized for the routine analysis of gasoline oxygenates and by-products in groundwater and reagent water. A sodium chloride concentration of 25%(w/w) combined with an extraction time of 20 min provided the greatest sensitivity while maintaining analytical efficiency Replicate analyses in fortified reagent and groundwater spiked with microgram per liter concentrations of gasoline oxygenates and by-products indicate quantitative and reproducible recovery of these and related oxygenate compounds. Method dynamic range was 50$\mu\textrm{g}$ L-1 to 3000$\mu\textrm{g}$ L-1 for gasoline oxygenates and by-products.

• Environmental Analysis Health and Toxicology
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• 제15권1_2호
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• pp.53-59
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• 2000

The purpose of this study is the development of the simple and precise determination method of ethyl isocyanate (EIC) and propyl isocyanate (PIC) through derivatization using secondary aliphatic amines by gas chromatography with flame ionization detector. The urea derivatives are quantitatively and simultaneously derived from EIC and PIC with secondary aliphatic amines such as dipropylamine, dibutylamine. and dipentylamine in methylene chloride, and confirmed by thin layer chromatography and gas chromatography with mass selective detector. For GC/FID, according to the increasing carbon atom of the amines, the retention time and peak area of the urea derivatives are increased. The instrumental detection limits for EIC and PIC were about 23.3∼34.8 $\mu\textrm{g}$ and 21.6∼28.9 $\mu\textrm{g}$, respectively.

• 분석과학
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• 제8권4호
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• pp.807-814
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• 1995

Accurate measurements of ozone precursors are required to understand the process and extent of ozone formation in rural and urban areas. Nonmethane hydrocarbons (NMHCs) have been identified as important ozone precursors. Identification and quantification of NMHCs are difficult because of the large number present and the wide molecular weight range encountered in typical air samples. A major plan of the research team of the Climate and Air Quality Taiwan Station (CATs) was the measurement of atmospheric nonmethane hydrocarbons. An analytical method has been development for the analysis of the individual nonmethane hydrocarbons in ambient air at ppb (v) and subppb(v) levels. The whole ambient air samples were collected in canisters and analyzed by GC-FID with $Al_2O_3$/KCl PLOT column. Our targeted for quantitative analysis 43 compounds that may be substantial contributors to ozone formation. The retention indices and molar response factors of some commercially available $C_2{\sim}C_{10}$ hydrocarbons were determined and used to identify and quantify air samples. A quality assurance program was instituted to ensure that good measurements were made by participating in the International Nonmethane Hydrocarbon Intercomparison Experiments (NOMHICE).

• KSBB Journal
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• 제30권4호
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• pp.141-147
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• 2015

The convenient determination of methylsulfonylmethane (MSM) for a commercially available dietary supplement was developed using gas chromatography (GC)-flame ionization detector (FID). Chromatography was performed on a capillary column ($0.32mm\;I.D{\times}30m$, $0.25{\mu}m$) coated with dimethylpolysiloxane using diethylene glycol methyl ether as an internal standard. The performance characteristics of GC were evaluated in terms of selectivity, linearity, precision, accuracy, recovery, limit of detection (LOD) and limit of quantification (LOQ). The calibration curve was highly linear (the coefficient of determination: 0.9979) within the concentration range of $10.0{\sim}800.0{\mu}g/mL$ for MSM. The recoveries for three fortified concentrations were 96.7~97.1%, 96.6~97.3% and 96.8~97.2%, respectively. The LOD and LOQ of the method were $0.29{\mu}g/mL$ and $0.97{\mu}g/mL$, respectively. All obtained results were acceptable according to the guidelines of the Association of Official Analytical Chemists for dietary supplements. Thus, the validated analytical method using the GC-FID system is suitable for the determination of MSM in dietary supplement formulations for quality control.

• 한국식품위생안전성학회지
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• 제36권1호
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• pp.34-41
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• 2021

본 연구는 조제유류 중 지방산에 대해 최신 분석법을 마련하고자 수행하였다. 조제유류 중 지방산 함량 분석을 위해 GC를 이용한 분석법을 확립하고 시중에 유통 중인 제품을 대상으로 적용성을 검토하였다. 분석법 검증은 특이성, 직선성, 검출한계 및 정량한계, 정확성, 정밀성에 대해 수행되었다. Linoleic acid 및 α-linolenic acid의 0.1-5 mg/mL 농도범위에서 R2=0.999 이상의 우수한 직선성을 확인할 수 있었다. Linoleic acid 및 α-linolenic acid의 LOD는 각각 0.06 mg/mL, 0.01 mg/mL, LOQ는 각각 0.16 mg/mL, 0.03 mg/mL였다. 표준인증물질 분석을 통해 정확성을 검토하였으며, linoleic acid 및 α-linolenic acid의 회수율은 각각 100.8%와 101.1%로 확인하였다. 정밀성을 검토한 결과 시료 채취량에 따른 반복성은 linoleic acid 1.4-2.9%, α-linolenic acid 1.1-2.7%이었고, 실험실간 재현성은 각각 2.8%, 1.5%임을 확인하였다. 본 연구에서 확립된 분석법을 적용하여 국내 유통 중인 조제유류 및 조제식 제품 12건에 대해 적용성 검토를 실시한 결과 전체 시료에서 분석이 용이하였으며, 모두 기준·규격에 적합함을 확인하였다. 본 결과로부터 확립된 GC를 이용한 분석법은 조제유류 중 지방산 함량을 확인하기에 적합함을 확인하였으며 국내 식품 영양성분의 관리 기반을 강화하는데 기여할 것으로 사료된다.

• Advances in environmental research
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• 제4권1호
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• pp.39-48
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• 2015

Bisphenol A is widely used in plastic and other industrial consumer products. Release of bisphenol A and its analogues into the aquatic environment during manufacture, use and disposal has been a great scientific and public concern due to their toxicity and endocrine disrupting effects on aquatic wildlife and even human beings. More recent studies have shown that these alkylphenols may affect the molting processes and survival of crustacean species such as American lobster, crab and shrimp. In this study, we have developed gas chromatography with flame ionization detection (GC-FID) and gas chromatography-mass spectrometric (GC-MS) methods for the determination of bisphenol A and its analogues in shrimp Macrobrachium rosenbergii, blue crab Callinectes sapidus and American lobster Homarus americanus samples. Bisphenol A, 2,4-bis-(dimethylbenzyl)phenol and 4-cumylphenol were found in shrimp in the concentration ranges of 0.67-5.51, 0.36-1.61, and < LOD (the limit of detection)-1.96 ng/g (wet weight), and in crab of 0.10-0.44, 0.13-0.62, and 0.26-0.58 ng/g (wet weight), respectively. In lobster tissue samples, bisphenol A, 2-t-butyl-4-(dimethylbenzyl)phenol, 2,6-bis-(t-butyl)-4-(dimethylbenzyl)phenol, 2,4-bis-(dimethybenzyl)phenol, 2,4-bis-(dimethylbenzyl)-6-t-butylphenol and 4-cumylphenol were determined at the concentration ranges of 4.48-7.01, 1.23-2.63, 2.71-9.10, 0.35-0.91, 0.64-3.25, and 0.44-1.00 ng/g (wet weight), respectively. At these concentration levels, BPA and its analogs may interfere the reproduction and development of crustaceans, such as larval survival, molting, metamorphosis and shell hardening.

• 한국산업보건학회지
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• 제33권1호
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• pp.34-39
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• 2023

Objectives: In this study, the safety of alcohol-based hand sanitizers (ABHSs) for quasi-drugs and cosmetics was investigated by analyzing the ethanol content, which is an active ingredient with a sterilizing effect, and methanol, which is toxic. Methods: Forty-one ABHSs were purchased at large supermarkets and online stores. Ethanol quantification was performed by gas chromatography-flame ionization detector, and methanol quantification was performed by headspace-gas chromatography-mass spectrometry. Results: The ethanol content of ABHS in quasi-drugs was 49.6-67.8%, which was suitable for standard manufacturing procedures for external disinfectants, and the ethanol content of ABHS in cosmetics was 9.1-61.3%. The methanol content of ABHS in quasi-drugs ranged from not detected(N.D.)-131.8 ppm, which was suitable for the methanol detection standard of ethanol raw materials in the Korean Pharmacopoeia. The methanol content of ABHS in cosmetics was 23.4-859.7 ppm, which was suitable for the detection limit of methanol in cosmetics. Conclusions: The ethanol and methanol content of ABHS was judged to be safe. When selecting an ABHS to be used for sterilization, it seems necessary to check the content of ethanol, an active ingredient, and use it according to its intended purpose.

• 분석과학
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• 제14권2호
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• pp.180-190
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• 2001

화합물에 포함된 냄새를 유발하는 물질은 다양한 성분으로 되어 있다. 냄새를 유발하는 휘발성 화합물의 분석에는 GC 또는 GC/MSD 등이 많이 사용된다. 그러나, 이들 분석기기는 전체 휘발성 성분의 profile이나 특정성분의 함량을 정량적으로 분석할 수는 있으나, 냄새를 유발하는 지배적인 성분이 무엇인지 파악하기가 어렵다. 이러한 문제점을 해결하기 위해 사용되는 방법에는 GC-Sniffing 또는 GC-Olfactometry법 등이 있다. 본 연구에서는 복합적인 냄새성분을 검출하기 위해 사람의 후각을 이용하는 olfactometry를 기존 GC에 결합시켜 분리컬럼에서 분리된 시료가 동시에 검출되는 GC/FID/Olfactometry를 개발하였다. FID와 ODP 신호간의 시간차이는 물질의 종류와 농도, 그리고 패널에 따라 다르게 나타났다. 일반적으로 휘발성과 냄새강도는 큰 물질일수록, 패널의 호흡주기가 짧을수록 두 신호간의 시간차이가 적었다. 그러므로, 정확한 냄새 원인물질의 규명에는 이들 신호의 관계에 대한 고찰이 필요하다.

• 분석과학
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• 제30권4호
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• pp.174-181
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• 2017

Bio-liquid is a liquid by-product of the hydrothermal carbonization (HTC) reaction, converting wet biomass into solid hydrochar, bio-liquid, and bio-gas. Since bio-liquid contains various compounds, it requires efficient sampling method to extract the target compounds from bio-liquid. In this research, fatty acid methyl ester (FAME) in bio-liquid was extracted based on hollow fiber supported liquid phase microextraction (HF-LPME) and determined by Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography/Mass Spectrometry (GC/MS). The well-known major components of biodiesel, including methyl myristate, palmitate, methyl palmitoleate, methyl stearate, methyl oleate, and methyl linoleate had been selected as standard materials for FAME analysis using HF-LPME. Physicochemical properties of bio-liquid was measured that the acidity was 3.30 (${\pm}0.01$) and the moisture content was 100.84 (${\pm}3.02$)%. The optimization of HF-LPME method had been investigated by varying the experimental parameters such as extraction solvent, extraction time, stirring speed, and the length of HF at the fixed concentration of NaCl salt. As a result, optimal conditions of HF-LPME for FAMEs were; n-octanol for extraction solvent, 30 min for extraction time, 1200 rpm for stirring speed, 20 mm for the HF length, and 0.5 w/v% for the concentration of NaCl. Validation of HF-LPME was performed with limit of detection (LOD), limit of quantitation (LOQ), dynamic range, reproducibility, and recovery. The results obtained from this study indicated that HF-LPME was suitable for the preconcentration method and the quantitative analysis to characterize FAMEs in bio-liquid generated from food waste via HTC reaction.

• Journal of Microbiology and Biotechnology
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• 제19권12호
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• pp.1672-1678
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• 2009

We studied the effects of aged total petroleum hydrocarbons (aged TPH) on the survival of allochthonous diesel-degrading Rhodococcus sp. strain YS-7 in both laboratory and field investigations. The aged TPH extracted from a crude-oil-contaminated site were fractionized by thin-layer chromatography/flame ionization detection (TLC/FID). The three fractions identified were saturated aliphatic (SA), aromatic hydrocarbon (AH), and asphaltene-resin (AR). The ratio and composition of the separated fractions in the aged TPH were quite different from the crude-oil fractions. In the aged TPH, the SA and AH fractions were reduced and the AR fraction was dramatically increased compared with crude oil. The SA and AH fractions (2 mg/l each) of the aged TPH inhibited the growth of strain YS-7. Unexpectedly, the AR fraction had no effect on the survival of strain YS-7. However, crude oil (1,000 mg/l) did not inhibit the growth of strain YS-7. When strain YS-7 was inoculated into an aged crude-oil-contaminated field and its presence was monitored by fluorescent in situ hybridization (FISH), we discovered that it had disappeared on 36 days after the inoculation. For the first time, this study has demonstrated that the SA and AH fractions in aged TPH are more toxic to an allochthonous diesel-degrading strain than the AR fraction.