TY - JOUR
T1 - Determination of 19-nortestosterone, testosterone and trenbolone by gas chromatography-negative-ion mass spectrometry after formation of the pentafluorobenzylcarboxymethoxime-trimethylsilyl derivatives
AU - Bagnati, Renzo
AU - Fanelli, Roberto
PY - 1991/6/28
Y1 - 1991/6/28
N2 - The known reaction of 3-ketosteroids with carboxymethoxylamine (to form the corresponding carboxymethoximes), followed by esterification of the carboxyl group with pentafluorobenzyl bromide, has been used to obtain derivatives of 19-nortestosterone, testosterone and trenbolone suitable for high-sensitivity detection with gas chromatography-negative-ion chemical ionization mass spectrometry. These derivatives, after further silylation of the alcoholic groups of the steroids, showed excellent chromatographic and spectrometric characteristics and were detectable in the low picogram range. The derivatization gave rise to the formation of two isomers which were distinguishable by gas chromatography. The existence of the two isomers was also confirmed by high-performance liquid chromatography. Examples of the usefulness of this derivatization procedure are given for the analysis of 19-nortestosterone, testosterone and trenbolone in meat and urine samples. By the use of immunoaffinity extraction and addition of deuterated internal standards (synthesized by isotopic exchange), the new derivatization procedure allowed a correct identification and quantitation of the steroids and reached very low detection limits [0.02 ppb (109) for 19-nortestosterone and testosterone, 0.06 ppb for trenbolone].
AB - The known reaction of 3-ketosteroids with carboxymethoxylamine (to form the corresponding carboxymethoximes), followed by esterification of the carboxyl group with pentafluorobenzyl bromide, has been used to obtain derivatives of 19-nortestosterone, testosterone and trenbolone suitable for high-sensitivity detection with gas chromatography-negative-ion chemical ionization mass spectrometry. These derivatives, after further silylation of the alcoholic groups of the steroids, showed excellent chromatographic and spectrometric characteristics and were detectable in the low picogram range. The derivatization gave rise to the formation of two isomers which were distinguishable by gas chromatography. The existence of the two isomers was also confirmed by high-performance liquid chromatography. Examples of the usefulness of this derivatization procedure are given for the analysis of 19-nortestosterone, testosterone and trenbolone in meat and urine samples. By the use of immunoaffinity extraction and addition of deuterated internal standards (synthesized by isotopic exchange), the new derivatization procedure allowed a correct identification and quantitation of the steroids and reached very low detection limits [0.02 ppb (109) for 19-nortestosterone and testosterone, 0.06 ppb for trenbolone].
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U2 - 10.1016/S0021-9673(01)88656-8
DO - 10.1016/S0021-9673(01)88656-8
M3 - Article
C2 - 1894722
AN - SCOPUS:0025793645
VL - 547
SP - 325
EP - 334
JO - Journal of Chromatography A
JF - Journal of Chromatography A
SN - 0021-9673
IS - C
ER -