title: LC-MS/MS quantitation of plasma progesterone in cattle.
abstract: Quantitation of progesterone (P(4)) in biological fluids is often performed by radioimmunoassay (RIA), whereas liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) has been used much less often. Due to its autoconfirmatory nature, LC-MS/MS greatly minimizes false positives and interference. Herein we report and compare with RIA an optimized LC-MS/MS method for rapid, efficient, and cost-effective quantitation of P(4) in plasma of cattle with no sample derivatization. The quantitation of plasma P(4) released from three nonbiodegradable, commercial, intravaginal P(4)-releasing devices (IPRD) over 192 h in six ovariectomized cows was compared in a pairwise study as a test case. Both techniques showed similar P(4) kinetics (P > 0.05) whereas results of P(4) quantitation by RIA were consistently higher compared with LC-MS/MS (P < 0.05) due to interference and matrix effects. The LC-MS/MS method was validated according to the recommended analytical standards and displayed P(4) limits of detection (LOD) and quantitation (LOQ) of 0.08 and a 0.25 ng/mL, respectively. The high selective LC-MS/MS method proposed herein for P(4) quantitation eliminates the risks associated with radioactive handling; it also requires no sample derivatization, which is a common requirement for LC-MS/MS quantitation of steroid hormones. Its application to multisteroid assays is also viable, and it is envisaged that it may provide a gold standard technique for hormone quantitation in animal reproductive science studies.
authors.affiliation: ThoMSon Mass Spectrometry Laboratory, Institute of Chemistry, University of Campinas-UNICAMP, Campinas, SP, Brazil.
authors.forename: R M T
authors.initials: RM
authors.lastname: Fernandes
authors.forename: G C
authors.initials: GC
authors.lastname: Gomes
authors.forename: A M
authors.initials: AM
authors.lastname: Porcari
authors.forename: J R V
authors.initials: JR
authors.lastname: Pimentel
authors.forename: P M
authors.initials: PM
authors.lastname: Porciúncula
authors.forename: H A
authors.initials: HA
authors.lastname: Martins-Júnior
authors.forename: P H P
authors.initials: PH
authors.lastname: Miguez
authors.forename: J L
authors.initials: JL
authors.lastname: da Costa
authors.forename: P H
authors.initials: PH
authors.lastname: Amaral
authors.forename: F
authors.initials: F
authors.lastname: Perecin
authors.forename: E C
authors.initials: EC
authors.lastname: Meurer
authors.forename: P V
authors.initials: PV
authors.lastname: Furtado
authors.forename: R C
authors.initials: RC
authors.lastname: Simas
authors.forename: M N
authors.initials: MN
authors.lastname: Eberlin
authors.forename: C R
authors.initials: CR
authors.lastname: Ferreira
authors.forename: E H
authors.initials: EH
authors.lastname: Madureira
mesh_terms: D000818:Animals; D002417:Cattle; D002853:Chromatography, Liquid / Q000379:methods / Q000662:veterinary*; D004973:Estrus Synchronization / Q000379:methods; D005260:Female; D011374:Progesterone / Q000097:blood*; D053719:Tandem Mass Spectrometry / Q000379:methods / Q000662:veterinary*
chemical_list: D011374:Progesterone