TY - JOUR
T1 - Multiplexed quantitation of endogenous estrogens and estrogen metabolites in human peritoneal fluid
AU - Xu, Xia
AU - Othman, Essam El Dine R.
AU - Issaq, Haleem J.
AU - Hornung, Daniela
AU - Al-Hendy, Ayman
AU - Veenstra, Timothy D.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2008/6
Y1 - 2008/6
N2 - Endogenous estrogens and estrogen metabolites (EM) in human peritoneal fluid may play an important role in health and disease, yet little is known regarding their types and levels present in human peritoneal fluid, primarily due to the lack of an analytical method that is capable of directly quantifying their absolute abundances. In this report, we describe the application of a capillary LC-MS/MS method for identifying and quantifying biologically active and total endogenous EM in human peritoneal fluid. The method requires only 50 μL of peritoneal fluid, yet can quantify 13 distinct EM. Calibration curves for each EM were linear over a 103-fold concentration range and the lower LOQ was 50 fg on-column. For charcoal stripped human peritoneal fluid sample containing 10 pg/mL of each EM, accuracy ranged from 83 to 118%, and intrabatch precision ranged from 0.2 to 4.4% RSD and interbatch precision ranged from 5.5 to 15.5% RSD. The analyses of human female peritoneal fluid shows that at least 10 biologically active and 11 total endogenous EM can be positively identified and quantitatively measured. Many of the biologically active forms are present in high abundance and possess distinct biological activities which warrant further study. Although micellar EKC gave baseline separation of a standard mixture of 10 EM, the LOQs using UV detection were not suitable for the assay of the low level estrogens in biological samples.
AB - Endogenous estrogens and estrogen metabolites (EM) in human peritoneal fluid may play an important role in health and disease, yet little is known regarding their types and levels present in human peritoneal fluid, primarily due to the lack of an analytical method that is capable of directly quantifying their absolute abundances. In this report, we describe the application of a capillary LC-MS/MS method for identifying and quantifying biologically active and total endogenous EM in human peritoneal fluid. The method requires only 50 μL of peritoneal fluid, yet can quantify 13 distinct EM. Calibration curves for each EM were linear over a 103-fold concentration range and the lower LOQ was 50 fg on-column. For charcoal stripped human peritoneal fluid sample containing 10 pg/mL of each EM, accuracy ranged from 83 to 118%, and intrabatch precision ranged from 0.2 to 4.4% RSD and interbatch precision ranged from 5.5 to 15.5% RSD. The analyses of human female peritoneal fluid shows that at least 10 biologically active and 11 total endogenous EM can be positively identified and quantitatively measured. Many of the biologically active forms are present in high abundance and possess distinct biological activities which warrant further study. Although micellar EKC gave baseline separation of a standard mixture of 10 EM, the LOQs using UV detection were not suitable for the assay of the low level estrogens in biological samples.
KW - Capillary liquid chromatography
KW - Electrospray ionization-tandem mass spectrometry
KW - Endogenous estrogens and estrogen metabolites
KW - Human peritoneal fluid
KW - Selected reaction monitoring
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U2 - 10.1002/elps.200700837
DO - 10.1002/elps.200700837
M3 - Article
C2 - 18512681
AN - SCOPUS:46249112359
VL - 29
SP - 2706
EP - 2713
JO - Electrophoresis
JF - Electrophoresis
SN - 0173-0835
IS - 12
ER -