Kim, JY Choi, MH Kim, SJ Chung, BC 2024-01-21T14:37:26Z 2024-01-21T14:37:26Z 2021-09-05 2000-01 0951-4198 https://pubs.kist.re.kr/handle/201004/141701 A high-performance liquid chromatographic-tandem mass spectrometric (HPLC/MS/MS) method for the determination of 19-nortestosterone and its esters (cyclopentanepropionate, phenylpropionate, and decanoate) in equine plasma is achieved using an atmospheric pressure chemical ionization (APCI) interface in selected reaction monitoring (SRM) mode. The two internal standards used were 16,16,17-H-2(3)-19-nortestosterone for 19-nortestosterone and methenolone acetate for its esters, The steroids studied were extracted from plasma samples with a mixture of diethyl ether/n-hexane (9:1, v/v), The quantification limits for 19-nortestosterone, 19-nortestosterone cyclopentanepropionate, 19-nortestosterone phenylpropionate, and 19-nortestosterone decanoate were 0.16, 5.0, 0.1, and 2.0 ng/mL, respectively, when 2 mt of plasma were used, The recoveries of most of the steroids were 71.6-101.0% except for the decanoate, which could be recovered to about 39.8%. The responses were linear, with correlation coefficients varying from 0.9897 to 0.9999 in the concentration range of 0.1 to 50.0 ng/mL for the steroids studied. When applied to equine (mare) plasma samples, the present method allowed detection of 19-nortestosterone up to 23 days after an intra-muscular injection of 400 mg as the decanoate, Copyright (C) 2000 John Wiley & Sons, Ltd. English JOHN WILEY & SONS LTD ANABOLIC-STEROIDS NEUTRAL STEROIDS URINE IDENTIFICATION TESTOSTERONE METABOLITES HORSE Measurement of 19-nortestosterone and its esters in equine plasma by high-performance liquid chromatography with tandem mass spectrometry Article 10.1002/1097-0231(20001015)14:19<1835::AID-RCM103>3.0.CO;2-I 1 RAPID COMMUNICATIONS IN MASS SPECTROMETRY, v.14, no.19, pp.1835 - 1840 RAPID COMMUNICATIONS IN MASS SPECTROMETRY 14 19 1835 1840 scie scopus 000089584400015 2-s2.0-0033799443 Biochemical Research Methods Chemistry, Analytical Spectroscopy Biochemistry & Molecular Biology Chemistry Spectroscopy Article ANABOLIC-STEROIDS NEUTRAL STEROIDS URINE IDENTIFICATION TESTOSTERONE METABOLITES HORSE 19-nortestosterone equine plamsa