• 한국식품위생안전성학회지
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• 제8권1호
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• pp.17-23
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• 1993

In an attempt to quantitate and qualitate residual antibiotics and antibacterial agents n meat simultaneously, we studied a gas chromatogrphy-mass spectrometry (GC/MS) analysis. For a simultaneous analysis of macrolide antibiotics such as erythromycin and tylosin in meat, the homogenization with MeOH, defatting with n-hexane, extraction with CHCl3, elution with CHCl3 : MeOH=2:1 from Sep-Pak silica cartridge, acid gydrolysis, back extraction with CHCl3, and quantitation by selected ion monitoring(SIM) mode after trimethylsilyl derivatization were performed. The recoveries of erythromycin and tylosin (CV,%) at 10 ppm fortification level were 90.59(4.89) and 45.91(0.20) , and the detection limits of those were 0.02 and 2.0 $\mu\textrm{g}$/g beef, respectively. From these results, the developed analytical method using GC/MS-SIM mode allows excellent detection and quantitation of residual macrolide antibiotics in meats, using complementary method with bio-assay.

• Mass Spectrometry Letters
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• 제1권1호
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• pp.29-32
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• 2010

Cross reacting antibodies can cause an overestimation of the results of immunoassays. Therefore, alternative methods are needed for the accurate quantification of steroids. Gas chromatography combined with isotope-dilution mass spectrometry (GC-IDMS) is developed to quantify urinary active androgens, testosterone, epitestosterone and dihydrotestosterone, which are clinically relevant androgens to both hair-loss and prostate diseases. The method devised involves enzymatic hydrolysis with $\beta$-glucuronidase, solid-phase extraction, liquid-liquid extraction using methyl tert-butyl ether and subsequent conversion to pentafluorophenyldimethylsilyl-trimethylsilyl (flophemesyl-TMS) derivatives for sensitive and selective analysis in selected-ion monitoring mode. Flophemesyl-TMS derivatization not only eliminates matrix interference but also has a good peak resolution within a 6 min-run. A selective and sensitive GC technique with flophemesyl-TMS derivatives also allows accurate quantitative analysis of three active androgens when combined with IDMS. The limit of quantification of the three analytes was <50 pg/mL, and extraction recoveries ranged from 91.9 to 102.1%. The precision and accuracy were 1.2~6.5% and 89.0~106.7%, respectively. This GC-IDMS method can be useful for evaluating the drug efficacy and monitoring the biological processes responsible for male-pattern baldness and prostate diseases.

• 한국식품과학회지
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• 제39권4호
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• pp.360-365
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• 2007

간장 중 3-MCPD 분석을 위한 HFBI, PBA, BSTFA 및 MBTFA를 사용한 유도체화 방법 및 시료 정제를 위한 흡착제, 용출용매 및 Surrogate, 내부표준물질 등을 검증한 결과 MBTFA를 이용한 acylation 방법을 제외한 나머지 세가지 유도체화 방법 모두 0.01 mg/kg 이하의 검출한계를 확인하였으며 정량한계(검출한계 ${\times}$3배)를 고려하더라도 현재의 국내 0.3 mg/kg 기준을 분석하는데 문제가 없는 것으로 판단되었으나 유럽의 허용치 0.02 mg/kg을 분석하기 위해서는 PBA방법이나 BSTFA를 사용한 유도체화 방법의 경우 최종 시료액을 약 5배 이상 농축할 필요가 있다. 한편, 유도체화를 위한 반응조건으로 가열시간 및 온도는 HFBI와 BSTFA를 사용하는 경우 $70^{\circ}C$에서 각각 30 및 60분 그리고 PBA는 첨가 직후부터 가열 없이 반응이 완결되는 것으로 나타났다. 흡착제는 Extrelut20 혹은 Florisil 이 가장 적합한 것으로 확인되었으며, 흡착제로부터의 3-MCPD 용출용매로는 ethyl acetate가 상대적으로 높은 추출능을 보여 주었다. 또한 고가의 3-MCPD 중수 소치환 동위원소 surrogate 물질을 대체하기 위한 surrogate 표준물질로는 1,2-butanediol이 그리고 내부표준물질로는 1,2-dibromo-3-chloropropane이 가장 적합한 것으로 확인하였다.

• 대한유전성대사질환학회지
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• 제15권3호
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• pp.138-146
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• 2015

Purpose: If early diagnosis is not made, patients with metabolic disorders as homocystinemia rapidly progress to physical defect or mental retardation resulted in storage of the toxic material into the brain. Therefore, it is necessary to develop an analytical method for a rapid screening and/or correct confirmation diagnosis. Methods: The standard solution of sulfur amino acids spiked plasma was subjected to protein precipitation with methanol, and then consecutively derivatized with trimethylsilyl (TMS) and trifluoroacyl (TFA) and determined by GC-MS. The formation of TMS derivative of the hydroxyl and TFA derivative of amino functional group was performed by BSTFA and MBTFA, respectively. Selective ion monitoring (SIM) mode was used for quantification with selected specific ions. Results: A calibration curve on standard spiked pooled plasma showed a linear relationship with correlation coefficient of 0.9936-0.9992 for all compounds over the range of 0.1-300 ng. The precision and accuracy were within S.D. of 1-15% and RSD of 1-15% for intra-day assay at 2 ng/mL, 15 ng/mL and 30 ng/mL. LOD and LOQ was 0.4 ng/mL and 4 ng/mL respectively. Conclusion: A rapid analytical method was developed to quantify sulfur amino acids and methyl malonic acid, after two-step derivatization procedure with good sensitivity and specificity on human plasma. Advantages of a new method are simplicity and rapidity. The method could be useful for routine analysis, diagnosis of homocysteinemia.

• 분석과학
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• 제13권4호
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• pp.484-493
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• 2000

생물시료 중 존재하는 알킬페놀류, 클로로페놀류 및 비스페놀 A의 동시분석을 기체크로마토그래피-질량분석기-선택이온검색법에 의해 수행하였다. 시료 중 페놀류는 유기용매로 추출하고 정제과정은 Florisil과 silica 컬럼을 비교분석하였다. 회수율 실험은 각 생물시료에 1-ppm 정도를 첨가하여 수행하였다. 이들의 회수율은 83-116% 정도로 나타났고, 표준편차는 약 2.4-11.9%로 나타났다. 페놀류의 검출한계를 증진시키기 위하여, trimeaylsilyl(TMS) 유도체 방법을 도입하였다. 유도체화 시키지 않은 페놀과 TMS 유도체화된 페놀류의 기체크로마토그래피 성질을 연구하였다.

• 한국식품위생안전성학회지
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• 제21권3호
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• pp.153-158
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• 2006

2005년 6월부터 9월까지 경기도내에서 유통되고 있는 간장류 105개에 대하여 CC-MSD을 이용하여 3-MCPD와 1,3-DCP의 오염도를 살펴보았다. 간장에 대한 3-MCPD의 검출률을 살펴보면 17.1%로 나타났고 검출수준은 최저 0.02mg/kg에서 최고 0.27mg/kg이였다. 식품공전에 고시된 잠정허용기준(0.3mg/kg)을 초과하는 검체는 없었고 1,3-DCP는 모든 시료에서 검출되지 않았다. 본 연구에서는 유도체화 방법으로 정량성 있는 BSA를 이용한 Silylation방법을 이용하였는데 이는 유도체 반응 후에 후 처리할 필요가 없어 비교적 간편하게 이용되는 방법이다. BSA-MCPD와 BSA-DCP의 머무름 시간은 11.30min, 10.12min이며 BSA-MCPD와 BSA-DCP의 mass spectra상에서 각각 m/z 147, 219, 239, 103, 116, m/z 93, 165, 95, 151, 185, 149들이 특징적인 이온으로 나타났다. BSA-MCPD의 주된 이온인 m/z 147은 $(CH_3)_3Si-O+=Si(CH_3)_2$로 TMS유도체의 특징적인 이온이다. 또한 TMS유도체의 구조 규명에 손쉽게 사용될 수 있는 $(M-15)^+$ 이온이 BSA-MCPD와 BSA-DCP에서 각각 m/z 239, 185로 확인되었다.

• 분석과학
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• 제11권5호
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• pp.374-385
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• 1998

주로 음식물의 섭취에 기인하는 phytoestrogen은 말초 신경 및 암 세포내에서 estrogen의 생성을 저해하거나, 농도를 감소시킴으로서 estrogen-dependent cancer의 잠재적인 항 증식 물질(antipromotional compound)로 알려지고 있으며, 이러한 이유로 estrogen 대사 과정에 대한 phytoestrogen의 관련성 여부가 연구의 대상이 되고 있다. 이에, 본 연구에서는 phytoestrogen과 estrogen 대사체들을 동시에 분석하기 위한 방법으로써 Serdolit AD-2 수지를 이용한 고체상 추출과 효소 가수분해, 액체-액체 추출 방법을 이용한 전처리 과정을 확립하였으며, 이를 MSTFA/TMCS 혼합액에 의해 trimethylsilyl(TMS) ether 형태로 유도체화 한 후 GC/MS의 SIM(selected ion monitoring) 방법으로 동시에 분석, 정량할 수 있는 조건을 설정하였다. 본 실험 방법의 정확도와 정밀도는 within-a day 및 day-to-day 시험으로 평가되었으며 회수율과 검출 한계는 각각 71.96~105.66%, 2~4 ng/mL 이었다. 이 방법을 이용하여 정상 성인 남녀의 뇨중에 존재하는 17종의 estrogen과 5종의 phytoestrogen 농도를 측정하였으며, 그 결과 남성과 여성의 뇨중 phytoestrogen과 estrogen의 농도 분포에 현저한 차이가 있음을 알 수 있었다.

• 분석과학
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• 제24권4호
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• pp.256-265
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• 2011

호박유물의 적절한 보존방안 마련에 필요한 호박의 화학적 분광학적 특성을 Infrared (IR) 분석과 pyrolysis/GC/MS (py/GC/MS) 분석을 통해 조사하였다. 호박 시료는 Baltic, Chiapas, Colombian, Dominican, Fushun, Madagascar 호박 등 6개의 산지에서 총 14종을 확보하였다. 시료의 비파괴적 조사를 위해 IR 분석을 실시하였고, 고분자 구성 성분 조사를 위해 py/GC/MS를 $300^{\circ}C$ 열분해 온도에서 온라인 trimethylsilylation을 통하여 분석하였다. IR 분석에서는 대체적으로 산지에 관계없이 유사한 스펙트럼을 보였으나, 지문영역에서는 Baltic 호박의 경우 Baltic shoulder에 해당하는 $1250cm^{-1}{\sim}1150cm^{-1}$에서 흡수가 나타나는 등 각각의 산지별로 구분이 가능한 차별화된 IR 스펙트럼이 관찰되었다. py/GC/MS 분석에서는 succinic acid, pimaric acid 등 호박의 구성성분으로 알려진 물질들이 검출되었고, Baltic, Chiapas, Fushun 호박의 경우 산지 구분이 가능한 특정성분이 검출되었다. 이러한 결과는 발견 및 발굴 유물에서 호박을 확인하거나, 산지 및 제작기술 추정 등 고고과학적인 해석의 기초 자료로 활용될 수 있을 것으로 기대된다.

• 한국산업보건학회지
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• 제9권1호
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• pp.23-40
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• 1999

The analysis of thiodiglycolic acid in urine has been used as an index of biological exposure to vinyl chloride. Unfortunately thiodiglycolic acid has a strong hydrophilic character, because it has two carboxylic groups, so that it can only be extracted with organic solvent with a great difficulty. Underivatized thiodiglycolic acid tends to tail because of non-specific interaction with the inert support. Therefore, esterification is the obvious first choice for derivatization of thiodiglycolic acid, particularly for gas chromatography. In this study, the focus of interest is to compare two method of esterifications (methylation and silylation). Methylation is to make the methyl ester of thiodiglycolic acid by reaction with diazomethane. Silylation is to make the trimethylsilyl ester of thiodiglycolic acid by reaction with N-trimethylsily-ldiethylamine. The results and conclusions are as the following: 1. The detection limit (sensitivity) of methylated thiodiglycolic acid was $5.00{\mu}g/m{\ell}$ and silylated thiodiglycolic acid was $3.07{\mu}g/m{\ell}$ by gas chromatography with flame ionization detector. 2. The optimal liquid-liquid extraction of thiodiglycolic acid was as following: To each of the tubes, $15m{\ell}$ of urine, concentrated sulfuric acid (pH 1 - 2) and 5 gsodium sulfate were added. The samples was extracted three times with $5m{\ell}$ ethylacetate each time. 3. The methylated thiodiglycolic acid was more stable than silylated thiodiglycolic acid in extractional solvent which contained humidity. 4. The precision (pooled coefficient of variation for 4 days) of the analysis was 0.07324 in methylated thiodiglycolic acid with external standard calibration, and 0.07033 in methylated thiodiglycolic acid with internal standard calibration. 5. The precision (pooled coefficient of variation for 4 days) of the analysis was 0.10914 in silylated thiodiglycolic acid with external standard calibration, and 0.13602 in silylated thiodiglycolic acid with internal standard calibration. From the above results, the analysis of methylated thiodiglycolic acid was more sensitive (limit of detection) than silylated thiodiglycolic acid by gas chromatography. However, the methylated thiodiglycolic acid was stable in the humidity and was separated sharply on chromatogram. Also, analysis of methylated thiodiglycolic acid was more precise (pooled coefficient of variation for 4 days) than silylated thiodiglycolic acid. In conclusion, it is established that the analysis of methylated thiodiglycolic acid is appropriate for biological monitoring of exposure to vinyl chloride.

• 약학회지
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• 제52권2호
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• pp.137-146
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• 2008

Even though driving under the influence of drug (DUID) is a worldwide problem, we, Korea has no regulation system yet except for alcohol, and there are little cases reported related to DUID. In order to investigate the type of abused drugs for drivers in Korea, we tried to analyze controlled and non-controlled drugs in alcohol-positive blood samples. 275 whole bloods, which were positive for alcohol on the roadside test, were collected from the police for two months ($Nov.{\sim}Dec.$ 2006). The analytical strategy was constituted of three steps: First, alcohol in blood samples were confirmed and quantified by gas chromatography. Second, controlled drugs were screened by $Evidence_{investigator}\;^{TM}$ (Randox, U.K.) as preliminary test. It was based on immunoassay by biochip array analyzer. Nine groups of drug abuse were screened: amphetamines, methamphetamines, cannabis, cocaine, opiates, barbiturates, methadone, benzodiazepines I (oxazepam) & II (lorazepam). Finally, confirmation of these drugs was performed by GC-MS. Blood samples were extracted by solid-phase extraction by $RapidTrace^{TM}$ (Zymark, U.S.A.). After trimethylsilyl (TMS) derivatization, eluates were analyzed to GC-MS. Total 49 drugs were investigated in this study including controlled drugs, antidepressants, 1st generation antihistamines, dextromethorphan, nalbuphine, ketamine, etc. For rapid detection, we developed the automated identification system. It was made up a new software, "DrugMan", modified Chemstation data analysis menu and newly developed macro modules. A series of peak selection, identification and reporting of the results were performed automatically by this system. Concentrations of alcohol in 275 blood samples were ranged from 0.011 to 0.249% (average, 0.119%). Among 149 blood samples, just six samples (4.0%) were showed positive results to the immunoassay: one methamphetamine and five benzodiazepines group I. By GC-MS confirmation, only benzodiazepines were detected and methamphetamine was not detected from immunoassay positive blood sample. Besides these drugs, 5 chlorpheniramines, dextromethorphan, diazepam, doxylamine, ibuprofen, lidocaine and topiramate were also detected in whole bloods by GC-MS. Conclusively, the frequency of drug abuse for Korean drivers was relatively low. There was none case which illegal drug was detected. However these results were limited to alcohol positive blood samples, so it is necessary to analyze more samples including alcohol negative blood.