BACKGROUND: Cholesterol and its metabolic precursors occurring in metabolic pathways are important biochemical indicators in pathological conditions. METHODS: A method for the simultaneous determination of cholesterol and its metabolic precursors, such as lanosterol and 7-dehydrocholesterol, in rat plasma is demonstrated. It involves their extraction after saponification, followed by conversion to tert-butyldimethylsilyl (TBDMS) derivatives for analysis by gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode (GC-SIM-MS). RESULTS: The characteristic fragment ions of [M-57], m/z 443, 483, and 441 permitted the accurate and selective detection of cholesterol and its precursors in rat plasma. The whole procedure of TBDMS derivatization, with subsequent GC-SIM-MS analysis, was linear (r>or=0.9994), reproducible (% relative standard deviation=2.2 to 7.5), and accurate (% relative error=-5.6 to 7.7), with detection limits of 0.02 to 0.07 ng/ml. Recoveries were measured to be ranged from 89.5 to 95.4%. CONCLUSION: The present method was useful for the quantification of cholesterol and its precursors in rat plasma samples of 1 microl.
BACKGROUND:Cholesterol and its metabolic precursors occurring in metabolic pathways are important biochemical indicators in pathological conditions. METHODS: A method for the simultaneous determination of cholesterol and its metabolic precursors, such as lanosterol and 7-dehydrocholesterol, in rat plasma is demonstrated. It involves their extraction after saponification, followed by conversion to tert-butyldimethylsilyl (TBDMS) derivatives for analysis by gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring (SIM) mode (GC-SIM-MS). RESULTS: The characteristic fragment ions of [M-57], m/z 443, 483, and 441 permitted the accurate and selective detection of cholesterol and its precursors in rat plasma. The whole procedure of TBDMS derivatization, with subsequent GC-SIM-MS analysis, was linear (r>or=0.9994), reproducible (% relative standard deviation=2.2 to 7.5), and accurate (% relative error=-5.6 to 7.7), with detection limits of 0.02 to 0.07 ng/ml. Recoveries were measured to be ranged from 89.5 to 95.4%. CONCLUSION: The present method was useful for the quantification of cholesterol and its precursors in rat plasma samples of 1 microl.
Authors: Hyesook Yoon; Erin M Triplet; Whitney L Simon; Chan-Il Choi; Laurel S Kleppe; Elena De Vita; Aubry K Miller; Isobel A Scarisbrick Journal: Glia Date: 2021-10-09 Impact factor: 7.452
Authors: Eef Boets; Sara V Gomand; Lise Deroover; Tom Preston; Karen Vermeulen; Vicky De Preter; Henrike M Hamer; Guy Van den Mooter; Luc De Vuyst; Christophe M Courtin; Pieter Annaert; Jan A Delcour; Kristin A Verbeke Journal: J Physiol Date: 2016-09-18 Impact factor: 5.182