• KSBB Journal
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• 제26권4호
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• pp.323-327
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• 2011

The convenient derivatization method of chiral amino alcohols as 9-anthraldimine Schiff base derivatives for chiral resolution was developed and the liquid chromatographic enantiomer separation of chiral amino alcohols as 9-anthraldimine derivatives was investigated on several coated and covalently bonded polysaccharide-derived chiral stationary phases (CSPs). In general, the performance of Chiralcel OD-H (or Chiralcel OD) (${\alpha}$ = 1.24-2.89), the coated CSP derived from cellulose derivative was superior to the other CSPs for resolution of 9-anthraldimine derivatives of several amino alcohols. The results of enantioseparation depending on the structure of 9-anthraldimine analytes like the steric bulky group and the polar moiety etc were discussed. The analytical method was applied to measure the enantiomeric purity of commercially available chiral amino alcohols. It is expected that the convenient analytical method will be very efficient for determination of enantiomeric purity of amino alcohols as 9-anthraldimine Schiff base derivatives with strong UV absorption.

• 한국환경보건학회지
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• 제32권1호
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• pp.67-70
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• 2006

A gas chromatography/mass spectrometric method was developed for the determination of formaldehyde in hair. 0.3mg of hair was placed in 10ml headspace vial. 1.5mM pentafluorophenylhydrazine solution (pH 2) in 0.03 M phosphoric acid and $20\;{\mu}l$ of 500 mg/l $acetone-d_6$ as internal standard were added in vial and sealed tightly with cap. The solution was heated for 30 min at $90^{\circ}C$ in heating block. The extraction, the derivatization and the evaporation were performed simultaneously. After heating of the solution, 0.5 ml of headspace was taken up and analyzed by gas chromatography-mass spectrometry (GC-MS). Low limit of detection (LaD) and Low limit of quantitation (LOQ) of formaldehyde were 0.5 and 1.5 ng/g, respectively. The method was used to analyze formaldehyde in rat hair after oral exposure. The developed method may be valuable to be used to analyze formaldehyde in human hair.

• 분석과학
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• 제36권4호
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• pp.143-151
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• 2023

Considering the greater role of α-amino acids in our daily lives, the enantiomer resolution of seven α-amino acids derivatized with fluorogenic reagent (4-fluoro-7-nitro-2,1,3-benzoxadiazole, NBD-F) by chiral HPLC on amylose or cellulose trisphenylcarbamate derived chiral stationary phases (CSPs) under simultaneous ultraviolet (UV) and fluorescence (FL) detection was performed. The degree of enantioseparation and resolution was affected by nature and selector backbones of the CSPs as well as the kind of amino acids. Baseline enantiomer separation and resolutions were observed for the enantiomers of all analytes as NBD derivatives especially on coated type amylose tris(3,5-dimethylphenylcarbamate) derived CSPs (Chiralpak AD-H and Lux Amylose-1). The other CSPs also showed good enantioselectivity except for the CSPs (Chiralpak IB, Chiralcel OD-H and Lux Cellulose-1) having cellulose tris(3,5-dimethylphenylcarbamate) as chiral selectors. The developed analytical chiral method was applied to determine the enantiomeric purity of seven commercially available L-α-amino acids and the impurities as D-forms were found to be in the range 0.08-0.87 %, respectively. The intra- and interday accuracy and precision assays showed high accuracy and precision of the developed analytical method. This chiral HPLC method for the enantiomer resolution of amino acids using fluorescent derivatization could be useful for the determination of enantiomeric purity of pharmaceuticals and biological study for amino acid type compounds among chiral drugs.

• 분석과학
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• 제18권5호
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• pp.444-451
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• 2005

참기름에서 스테롤류와 지방산을 간편하고 정확하게 추출하는 방법을 개발하였다. 새로운 방법은 특히 세사민의 추출 효율을 크게 향상하여 세사민과 캄파스테롤의 비율을 크게 향상시켜 감정의 도구로 응용이 가능할 것으로 판단되었다. 또 기타 스테롤류도 확인하였다. 유도체화를 진행시키면 지방산과 스테롤류의 동시 분석이 가능하였으나, 감정의 도구로는 더 많은 실험이 필요할 것으로 판단되었다.

• 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.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2005년도 국제학술대회
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• pp.337-340
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• 2005

Ethylene oxide is a genotoxic carcinogen with widespread uses as industrial chemical intermediate and gaseous sterilant. 2-hydroxyethylated N-terminal valine in Hb is a good biomarker for biological monitoring of ethylene oxide exposure, because of its stability. We studied the determination method of (N-2-hydroxy-ethyl)valine in hemoglobin adduct by using GC/MS. PFPITC and TBMS were used as appropriate derivatives. Ethylene oxide formed Hb adducts as (N-2-hydroxy-ethyl)valine(HEV) in mouse with ethylene oxide inhalation exposure. Standard HEV can be synthesized with 2-amino-ethanol and 2-bromo-3-methylbutyric acid. GC/MS can measured them after derivatization with pentafluorophenylisothiocianate(PFPITC) and N-(tertiary butyl dimethylsiiyl)-N-methyl-trifluoroacetamide(TBDMS-TFA) by using Edman procedure. Concentrations of Hb adduct were proportionally increased with exposure levels. They were 230${\pm}$35(nmol g$^{-1}$ globin) and 410${\pm}$72(nmol $g^{-1}$ globin) at 200ppm and 400ppm ethylene oxide inhalation exposure, respectively.

• Environmental Analysis Health and Toxicology
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• 제15권3호
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• pp.99-106
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• 2000

Ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) are various applied as chelating agents for metal ions, then they are widely used in many industrial processes and domestic products. A method is described for the determination of EDTA and NTA in water samples by GC/MS . The reaction temperature, reaction time and pH for esterification of EDTA and NTA were investigated using 10% sulfuric acid-methanol, ethanol and propanol. Optimum conditions were obtained by the esterification in 80$\^{C}$ for 1hr with ethanol. Method detection limits of ethylated EDTA and NTA in the 200 ml of water samples were 0.05 ng/ml, respectively, EDTA and NTA could be determined in the range of 0.05∼23.6 and 0.05∼7.0 ng/ml in treated water, and in the range of 0.06∼25.0 and 0.05∼6.40 ng/ml in raw water respectively. Risk assessments with EDTA and NTA exposure by drinking water ingestion were carried out. Based on the results of analysis, chronic daily intakes of EDTA and NTA would be less than the value of acceptable daily intake or tolerable daily intake.

• KSBB Journal
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• 제28권6호
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• pp.423-427
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• 2013

A new convenient derivatization method of ${\alpha}$-amino acid esters as nitrobenzoxadiazole (NBD) derivatives for chiral resolution was introduced and the enantiomer separation of ${\alpha}$-amino acid esters as NBD derivatives was performed by normal HPLC using chiral columns based on polysaccharide derivatives. The NBD derivatives were readily prepared by stirring NBD-Cl and ${\alpha}$-amino acid methyl ester HCl with $NaHCO_3$ in ethanol. The performance of Chiralpak IA was superior to the other chiral stationary phases for enantiomer resolution of NBD derivatives of several ${\alpha}$-amino acid methyl esters. Owing to fluorescence detection as well as strong UV absorption, it is expected that the convenient analytical method developed in this study will be very useful for enantiomer separation of ${\alpha}$-amino acid esters as NBD derivatives on polysaccharide-derived chiral columns.

• 대한유전성대사질환학회지
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• 제15권2호
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• pp.65-71
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• 2015

Since the secretion of specific chiral isomers in urine (or plasma) is very crucial to diagnose some inborn metabolic disorders, clinical application of dual column achiral differential method has been performed for the absolute configuration of chiral compounds. Extracted from the acidified urine with diethyl ether, carboxylic functional group of organic acid (stereoisomers of the volatile) was derivatized with (-)-menthylation or (S)-(+)-3-methyl-2-butylation and followed by O-trifluoroacylation. Each of the enantiomers was accurately separated from the library matched double column (achiral) with a retention index (I). In various inborn metabolic disease urines, absolute chirality was identified correctly in the urine (10 patients) with inborn metabolic disease (including secretion of D, L- lactic acid, D, L-3-hydroxybutyric acid, and D, L-2-hydroxyglutaric acid). In this study, we identified and isolated the volatile diastereomer as a useful diagnostic marker, this successful application to urine specimens may be useful for diagnostic classification of inherited metabolic disorders.

• 한국대기환경학회지
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• 제22권2호
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• pp.201-208
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• 2006

Several carbonyl compounds are important because of their irritant and toxic properties, mutagenicity and carcinogenicity. Therefore, they are regulated in korean odor emission standard. In this study, atmospheric pressure ionization-mass spectrometry(API-MS) is used for the analysis of carbonyl compounds after derivatization with 2, 4-dinitrophenylhydrazine (DNPH) and liquid chromatographic separation. In the negative ion mode, the $[M-H]^-$ pseudomolecular ions are most abundant for the carbonyls. Analytical parameters such as linearity, repeatability and minimum detection limit were evaluated. The linearities ($r^2$) for carbonyls were $0.9977{\sim}0.9999$ when analyte concentration ranges from $25\;to\;250{\mu}g/L$(n=6). The relative standard deviations (%RSD) for carbonyls were $0.55{\sim}3.51%$ for concentration of $100{\mu}g/L$(n=5). The minimum detection limit (MDL) was $1.88{\mu}g/L$(0.27 ppb) for i-valeraldehyde. It was shown that LC-MS method has a great potential for carbonyl compounds analysis.