PMID- 10596977
OWN - NLM
STAT- MEDLINE
DCOM- 20000124
LR  - 20190720
IS  - 0021-9673 (Print)
IS  - 0021-9673 (Linking)
VI  - 862
IP  - 2
DP  - 1999 Nov 12
TI  - New hydrolysis method for extremely small amount of lipids and capillary gas 
      chromatographic analysis as n(O)-tert.-butyldimethylsilyl fatty acid derivatives 
      compared with methyl ester derivatives.
PG  - 199-208
AB  - The organic basic solution, 1 M tetramethylammonium hydroxide (TMAH) in methanol, 
      was employed for the hydrolysis of extremely small amounts of lipids compared to 
      the classical inorganic basic solution, 1 M KOH in ethanol. The hydrolysed fatty 
      acids were derivatized as N(O)-tert.-butyldimethylsilyl (tBDMSi) esters with 
      N-methyl-N-(tert.-butyldimethylsilyl) trifluoroacetamide (MTBSTFA) and compared 
      with the classical derivatives, the methyl esters, made by the BF3-methanol 
      method. Recoveries of fatty acids determined on the standard fatty acids and 
      soybean oil hydrolysed with TMAH were high: about 1.1-2.1- and 2.0-5.4-times, 
      respectively, in all fatty acids compared with the hydrolysis by KOH regardless 
      of derivatization method. The relative standard deviations (RSDs) on the 
      recoveries of standard fatty acids were less than 5% when hydrolysed with TMAH, 
      regardless of derivatives, but when hydrolysed with KOH, RSDs were more than 5% 
      for most fatty acids, especially for long-chain fatty acids. The RSDs on the 
      recoveries of fatty acids on the soybean oil were also very high in the KOH 
      hydrolysis. Fatty acid compositions of soybean oil were similar in the main fatty 
      acids regardless of hydrolysis methods, but showed slightly different values, 
      depending on the methods of derivatization. RSDs were also very high in the KOH 
      hydrolysis. In view of these results, precision of analysis by KOH hydrolysis was 
      very poor, so we could not rely on the data. On the other hand, the reliability 
      of data by TMAH hydrolysis method was very high, so it is a useful new hydrolysis 
      method for extremely small amounts of lipid samples. Both derivatives of 35 
      standard fatty acids were successfully separated on a HP-1 nonpolar capillary 
      column. tBDMSi derivatives were completely resolved in 70 min by 295 degrees C. 
      In the methyl ester derivatives it took about 80 min to get satisfying 
      resolution, but these derivatives were completely resolved by 250 degrees C. The 
      sensitivity of tBDMSi derivatives was about 1.5-6.3-times higher than that with 
      methyl ester derivatives. The stability of tBDMSi derivatives was constant for 
      about 144 h except arachidic, docosahexanoic, behenic and heneicosanoic acids, 
      which were stable for only 86 h.
FAU - Woo, K L
AU  - Woo KL
AD  - Department of Food Engineering, Kyungnam University, Masan City, South Korea.
FAU - Kim, J L
AU  - Kim JL
LA  - eng
PT  - Journal Article
PL  - Netherlands
TA  - J Chromatogr A
JT  - Journal of chromatography. A
JID - 9318488
RN  - 0 (Acetamides)
RN  - 0 (Fatty Acids)
RN  - 0 (Fluoroacetates)
RN  - 0 (Hydroxides)
RN  - 0 (Indicators and Reagents)
RN  - 0 (Lipids)
RN  - 0 (Organosilicon Compounds)
RN  - 0 (Potassium Compounds)
RN  - 0 (Quaternary Ammonium Compounds)
RN  - 77377-52-7 (N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide)
RN  - 8001-22-7 (Soybean Oil)
RN  - H0W55235FC (tetramethylammonium)
RN  - WZH3C48M4T (potassium hydroxide)
SB  - IM
MH  - Acetamides
MH  - Chromatography, Gas
MH  - Fatty Acids/analysis
MH  - Fluoroacetates
MH  - Food Analysis/*methods
MH  - Hydrolysis
MH  - Hydroxides
MH  - Indicators and Reagents
MH  - Lipids/*chemistry
MH  - Organosilicon Compounds/*analysis
MH  - Potassium Compounds
MH  - Quaternary Ammonium Compounds
MH  - Soybean Oil/analysis
EDAT- 1999/12/22 00:00
MHDA- 1999/12/22 00:01
CRDT- 1999/12/22 00:00
PHST- 1999/12/22 00:00 [pubmed]
PHST- 1999/12/22 00:01 [medline]
PHST- 1999/12/22 00:00 [entrez]
AID - S0021-9673(99)00934-6 [pii]
AID - 10.1016/s0021-9673(99)00934-6 [doi]
PST - ppublish
SO  - J Chromatogr A. 1999 Nov 12;862(2):199-208. doi: 10.1016/s0021-9673(99)00934-6.