• Applied Biological Chemistry
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• v.35 no.2
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• pp.132-138
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• 1992

For effective determination of methylthiohydantoin amino acids(MTHs) by gas liquid chromatography in the protein sequencing, derivatization with N-methyl-N-(tert.-butyl-dimethylsilyl)trifluoroacetamide(MTBSTFA), a new silylating reagents, was attempted instead of trimethylsilyl(TMSi) derivatives by N,O-bis(trimethylsilyl)trifluoroacetamide(BSTFA) used up to the present and N(O)-butyldimethylsilyl MTHs derivatized by MTBSTFA were analysed on HP-1 capillary column. Twenty one protein amino acids except cystine were indentified. Especially arginine that did not detected with TMSi derivative on packed column until now was resolved by derivatization with MTBSTFA. N(O)-butyldimethylsilyl MTHs showed multiple peaks by MTBSTFA were proline, isoleucine, glycine and tyrosine and hydroxyproline especially showed several extraneous peaks more than two. Calibration curves of N(O)-butyldimethysilyl MTHs of amino acids in the range of $2.5\;nmol{\sim}7.5\;nmole$ showed good linearity. however, those of lysine, histidine and arginine showed linearity in the range of $5.0\;nmole{\sim}15.0\;nmole$. Correlation coefficients and regression coefficients of all calibration curves were highly significant(p<0.001).

• Journal of Food Hygiene and Safety
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• v.10 no.4
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• pp.239-247
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• 1995

Analytical method for saccharin in foods was developed using gas chromatography/mass spectrometry(GC/MS). Methylation with diazomethane, acetylation with MBTFA, and silylation with MSTFA and MTBSTFA were compared. Methylation of saccharin produced N-methylated saccharin as the major product and O-methylated saccharin as the minor one. Silylation of saccharin with MSTFA and MTBSTFA reasulted in the formation of the correponding O-silylated products, respectively. The derivatization of saccharin was optimized with MSTFA. The ions at m/z 240, 255, and 166 were monitored to characterize saccharin.

• 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.

• 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.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.17 no.2
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• pp.39-47
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• 2017

Purpose: A sensitive gas chromatography mass spectrometry (GC-MS) method was developed for screening of fatty acid oxidation disorders. Methods: The assay utilized a simple protein precipitation with sulfosalicylic acid followed by tert-butyl dimethylsilyl (TBDMS) derivatization of hydroxyl functional group by N-tert-butyldimethylsilyl-N-methyltrifluoroacetamide (MTBSTFA). Results: Calibration curves of spiked pooled plasma showed a linear relationship in the range of 0.01 ng -2 mg with correlation coefficient value greater than 0.98. Limits of detection (LOD) and limits of quantification (LOQ) were found in the range of 0.9-8.8 ng and 9-88 ng, respectively. Conclusion: The new developed method might be useful for a rapid, sensitive screening of inherited fatty acid oxidation disorders. In addition, the method expected to be one of the alternative method for screening newborns of metabolic disorders in the laboratories where expensive MS/MS is unavailable.

• Korean Journal of Food Science and Technology
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• v.39 no.4
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• pp.360-365
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• 2007

The studies for the derivatization of 3-monochloropropane-1,2-diol (3-MCPD) were performed mainly as acylation with HFBI (heptafluorobutyrylimidazole), alkylation with PBA (phenylboric acid) and silylation with BSTFA (N,O-bis[trimethylsilyl]trifluoroacetamide). Also silylation with MTBSTFA(N-methyl-N-[tert.-butyldimethylsilyl] trifluoroacetamide) and acylation with MBTFA (N-Methyl-bis[trifluoro-acetamide]) were also considered. Except the TBDMS derivative of 3-MCPD, all the derivatives were detected well. The derivatives of 3-MCPD with HFBI, PBA and BSTFA showed below 10 ${\mu}g/kg$ which was sensitive enough to satisfy Korea maximum residue limit 0.3 mg/kg. Among the tested adsorbents, Extrelut20 and Florisil were evaluated as the proper adsorbents to eliminate the soy sauce matrix for 3-MCPD. Ethyl acetate was the most efficient eluent with good recovery rate. The desired surrogate compound and internal standard were 1,2-butanediol and 1,2-dibromo-3-chloropropane, respectively. The limit of detection for PB-MCPD and TMS-MCPD were 10.16 and 7.06 ${\mu}g/kg$ on GC/MSD, respectively. HFB-MCPD derivative showed the lowest detection limits 2.98 and 5.32 ${\mu}g/kg$ by GC/ECD and GC/MSD, respectively.