• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2007년도 추계학술발표회
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• pp.35-41
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• 2007

An International Convention on the control of harmful anti-fouling system on ships(AFS Convention) was adopted on 5 October 2001 at Diplomatic Conference in London, and is expected to be presently effectuated with ratification of more than 25-member nations possessing about 25% of total world tonnage. This convention regulates the operation of harmful anti-fouling system and especially prohibits the use of organotin compounds contained in anti-fouling paint. Organotin compounds have a tendency to be easily extracted by specific solvents and have high polarity and low volatility as specific characteristics. This drives us to attempt of going through the process named derivatization that is required in analysis using a gas chromatography(GC). This study was conducted to determine the proper pre-treatment method, ethylation in comparison with hydridization on the analysis of tributyltin in organotin compounds and to verify the application of the method through the experimental analysis practically used anti-fouling paint and painted layer sample of the served ship.

• Biomolecules & Therapeutics
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• 제15권4호
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• pp.266-272
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• 2007

A rapid analytical method was developed to quantify very long-chain fatty acids (VLCFAs, C22:0, C24:0, C26:0) in human plasma with good sensitivity and specificity using tert-butyldimethylsilyl (TBDMS) derivatization and stable isotope GC-MS selective ion monitoring (GC-MS/SIM). Two-hundred and fifty ${\mu}L$ of plasma was fortified with deuterated stable isotope internal standards (d3-C22:0, d3-C24:0, d3-C26:0) and standard mixtures of chloroform and methanol, and then extracted with hexane and acetonitrile. To upper layer of liquid-liquid-extraction, N-(t-Butyldimethylsilyl)-N-methyltrifluoroacetamide was added and then heated to $60^{\circ}C$ for 30 min to produce the TBDMS derivatives. Derivatives of VLCFAs were analyzed by GC-MS/SIM. Calibration curves showed a linear relationship for the target compounds in the concentration range of $10^{-4}{\sim}2{\times}10^3\;{\mu}g/mL$ with the correlation coefficient ranging from 0.996 to 0.999. The limit of quantification for the plasma was $10^{-4}{\sim}2{\times}10^{-4}\;{\mu}g/mL$ (S/N=3). When applied to the plasma specimens of patients with peroxisomal disorder, X-linked adrenoleucodystropy (ALD, Mckusick 202370), the method clearly differentiated normal subjects from ALD patients. The C24:0/C22:0 and C26:0/C22:0 ratios were significantly elevated in the plasma of patients with X-linked ALD compared to normal subjects. The new developed method might be useful for a rapid and sensitive diagnosis of X-linked ALD and other peroxisomal disorders.

• Bulletin of the Korean Chemical Society
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• 제25권10호
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• pp.1508-1512
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• 2004

A gas chromatography/mass spectrometric (GC/MS) method has been developed for the determination of trace mono-n-butyltin (MBT), di-n-butyltin (DBT), and tri-n-butyltin (TBT) compounds in sediments. Samples were extracted by 10% acetic acid in methanol containing 0.03% tropolone and were then derivatized for GC/MS analysis. Ethylation by sodium tetraethylborate and phenylation by sodium tetraphenylborate were evaluated as a derivatization reaction of the organotins in sample extract. n-Hexane was added into reaction media in the beginning of the reaction for the continuous extraction of derivatized organotins. Ethylation requires less than 2 hours to get proper derivatization yields for MBT, DBT, and TBT altogether and produces relatively low amounts of side reaction products. Compared to ethylation, phenylation requires much longer time but provides relatively lower yield and produces considerable amounts of side reaction products. Therefore, the ethylation reaction was applied for the analysis of organotin compounds in sediment. An isotope dilution mass spectrometric (IDMS) method based on GC/MS has been applied to the accurate determination of DBT compounds in the sediments. The IDMS results from the analyses of sediment samples showed a reasonable repeatability and a good agreement with the values obtained by IDMS based on liquid chromatography/induced coupled plasma/mass spectrometry.

• 한국대기환경학회지
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• 제14권5호
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• pp.519-524
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• 1998

Formaldehyde is known to have adverse health effects, and is also found to be a product of atmospheric. photochemical reaction%. Several methods have been employed for the measurement of formaldehyde. Among them, two common methods are comparatively evaluated in this study, i.e. the chromotropic acid method and the HPLC method coupled with 2,4- dinitrophenylhydrazine (DNPH) derivatization of carbonyl compounds. Method evaluation and validation were performed with respect to repeatability, linearity, collection efficiency, and recovery efficiency. Comparison of formaldehyde concentrations measured simultaneously in the field using the two (n=20) and 35.8%, respectively. Overall, the measured levels by chromotropic acid method appeared to ice significantly higher than those by DNPH-HPLC method, indicating a positive interference due to the other aldehydes collected together with formaldehyde.

• 한국환경농학회지
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• 제13권2호
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• pp.199-208
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• 1994

토양 침투수중에 잔류하는 제초제 MCPP를 추출, 유도체를 합성하여 GC-MS로 확인하고 capillary GC-ECD로 잔류분석하였다. Diazomethane과 $BF_3$/MeOH 등을 이용하여 합성한 MCPP의 methyl 유도체, 황산을 촉매로 이용하여 합성한 MCPP의 2,2,2-trifluoroethyl(TFE) 및 2,2,2-trichloroethyl(TCE) 유도체, 그리고 MCPP의 pentafluorobenzyl(PFB) 유도체간의 잔류분석법을 비교한 결과 이 연구에서 개발된 MCPP-TFE 유도체화가 간편하고 신속, 안전한 유도체화 기술로서 GC-ECD에서 비교적 감도가 우수한 편이었다. MCPP의 methyl 유도체는 GC-ECD에서 그 감도가 너무 낮아 시료가 소량인 경우 ppb 수준의 잔류분석이 불가능하였고 MCPP-TCE 및 MCPP-PFB 유도체는 그 감도는 우수하였으나 크로마토그람상의 방해물질이 많아 액액분리에 의한 정제만으로는 잔류분석이 곤란하였다. MCPP-TFE 유도체화에 의하면 토양침투수 100ml중 $0.1{\mu}g$ 미만의 농도를 가진 MCPP의 잔류분석이 액액분리에 의한 정제만으로 가능하였다.

• 공업화학
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• 제21권2호
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• pp.200-204
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• 2010

고체 표면의 성질은 물질의 사용을 결정하는데 있어서 중요하다. 그래서 고분자 박막을 사용하여 표면을 개질시켜 표면층의 물리적, 화학적 성질을 제어하는 방법이 떠오르고 있다. 본 연구에서는 기판 표면과 고분자 간의 화학적 derivatization 없이 광화학 반응을 통하여 간단하고 효과적인 방법으로 고체 표면위에 고분자 박막을 흡착하여 표면을 개질시키는 방법을 설명하였다. 실리콘 웨이퍼에 스핀 코팅으로 형성된 광반응성이 있는 P4VP 박막을 이용하여 다른 고분자를 얹혀 UV 노광을 조사하여 벤질 라디칼 moieties 반응으로 고정하였다. 광화학 반응의 결과, UV 가교가 일어난 고분자는 P4VP 박막에 고정되어 지고, 반응이 일어나지 않은 부분은 초음파 세척으로 제거할 수 있다. 고정된 박막의 두께는 UV 노광 시간과 고분자의 분자량에 상관하여 형성되며, 광화학 반응으로 고정되기 때문에 photolithography 공정으로 마이크론 패턴 형성이 가능하다.

• Toxicological Research
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• 제31권3호
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• pp.313-319
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• 2015

3-Monochloro-1,2-propanediol (3-MCPD) and 1,3-dichloro-2-propanol (1,3-DCP) are not only produced in the manufacturing process of foodstuffs such as hydrolyzed vegetable proteins and soy sauce but are also formed by heat processing in the presence of fat and low water activity. 3-MCPD exists both in free and ester forms, and the ester form has been also detected in various foods. Free 3-MCPD and 1,3-DCP are classified as Group 2B by the International Agency for Research on Cancer. Although there is no data confirming the toxicity of either compound in humans, their toxicity was evidenced in animal experimentation or in vitro. Although few studies have been conducted, free 3-MCPD has been shown to have neurotoxicity, reproductive toxicity, and carcinogenicity. In contrast, 1,3-DCP only has mutagenic activity. The purpose of this study was to analyze 3-MCPD and 1,3-DCP in various foods using gas chromatography-mass spectrometry. 3-MCPD and 1,3-DCP were analyzed using phenyl boronic acid derivatization and the liquid-liquid extraction method, respectively. The analytical method for 3-MCPD and 1,3-DCP was validated in terms of linearity, limit of detection (LOD), limit of quantitation, accuracy and precision. Consequently, the LODs of 3-MCPD and 1,3-DCP in various matrices were identified to be in the ranges of 4.18~10.56 ng/g and 1.06~3.15 ng/g, respectively.

• 분석과학
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• 제13권5호
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• pp.636-645
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• 2000

본 연구에서는 GC/MS를 이용하여 수질시료로부터 7종의 유기주석화합물을 분석하는 방법을 연구하였다. Hydrogenation과 ethylation의 반응시의 pH, 반응시간, 반응시약의 농도 등을 변화시켜 최적 반응조건을 조사하였다. n-Hexane을 용매로 사용한 액체-액체 추출 후 hydrogenation에 의한 유기주석염화물의 추출 회수율은 61-112% 범위로 나타났다. 물시료에서 ethylation한 후 n-hexane으로 추출한 경우의 추출 회수율이 74-113% 범위로 나타나 hydrogenation의 경우보다 높은 추출율을 보였다. 또한 ethylation후 styrene-divinylbenzene (SDB) 재질의 disk형의 고체상을 사용하고 추출 용매로 methylene chloride를 사용한 경우 61-97% 범위의 회수율을 나타냈다. Hydrogenation과 ethylation에 의한 검출한계는 각각 0.05-0.5 ng/ml와 0.02-0.05 ng/ml로 나타났다.

• Korean Chemical Engineering Research
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• 제58권1호
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• pp.106-112
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• 2020

Analyzing vitamin D levels is important for monitoring health conditions because vitamin D deficiency is associated with various diseases such as rickets, osteomalacia, cardiovascular disorders and some cancers. However, vitamin D concentration in the blood is very low with optimal level of 75 nmol/L, making quantitative analysis difficult. The objective of this study was to develop a highly sensitive analysis method for vitamin D using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-MS). 25-hydroxyvitamin D (25(OH)D), which has been used as an indicator of vitamin D metabolites in human biofluids was chemically derivatized using a secosteroid signal enhancing tag (SecoSET) with powerful dienophile and permanent positive charge. The SecoSET-derivatized 25(OH)D provided good linearity (R² > 0.99) and sensitivity (limit of quantitation: 11.3 fmol). Chemical derivatization of deuterated 25-hydroxyvitamin D₃ (d₆-25(OH)D3) with SecoSET enabled absolute quantitative analysis using MALDI-MS. The highly sensitive method could be successfully applied into monitoring of quantitative changes of bioactive vitamin D metabolites after treatment with ketoconazole to inhibit 1α-hydroxylase reaction related to vitamin D metabolism in human breast cancer cells. Taken together, we developed a MALDI-MS-based platform that could quantitatively analyze vitamin D metabolites from cell products, blood and other biofluids. This platform may be applied to monitor various diseases associated with vitamin D deficiency such as rickets, osteomalacia and breast cancer.

• Environmental Analysis Health and Toxicology
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• 제15권1_2호
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• pp.39-43
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• 2000

Linear alkyl sulfonates (LAS) constitute a large fraction of the surfactants used in cleaning processes in households, trade and industry Despite the industrial significance and the possible environmental impact of these compounds, the fast and inexpensive determination of LAS concentrations is still a difficult task. In this study, near infrared (NIR) spectroscopy which is a rapid spectroscopic analysis method compared with a traditional analytical method for the measurement of LAS concentration such as HPLC, GC and standard wet chemistry method. NIR spectra of LAS between 0.313 and 25.0% (w/v) in water were utilized to develop a calibration model. The best results (R ＝ 0.998, SEP ＝ 0.244% (w/v)) obtained by using partial least-squares regression with spectral data treatment and 2nd derivatization were comparable to the results (SEC ＝ 0.186% (w/v), SEP ＝ 0.206% (w/v)) obtained by using multiple linear least-squares regression (MLR). However, models based on derivative spectra have no significant advantage with MLR.