title: Differentiation of monoiodothyronines using electrospray ionization tandem mass spectrometry.
abstract: In this work two monoiodothyronines, 3-T1 and 3'-T1, have been analyzed using electrospray ionization tandem mass spectrometry (ESI-MS/MS). Fragmentation patterns were proposed based on our data obtained by ESI-MS/MS. MS2 spectra in either negative or positive ion mode can be used to differentiate 3-T1 and 3'-T1. Based on the relative abundance of fragment ions in MS2 spectra in the negative ion mode, quantification of the 3-T1 and 3'-T1 isomers in mixtures is achieved without prior separation. Solid-phase extraction in combination with ESI-MS/MS provides a practicable procedure that can be used to determine the molar ratio of 3-T1 and 3'-T1 in human serum with an error less than 3%. The detection limits for 3-T1 and 3'-T1 were 0.5 and 0.7 pg/microL, respectively.
authors.affiliation: Division of Biology, Kansas State University, Manhattan, KS 66506-4901, USA. ytz@ksu.edu
authors.forename: Yuntao
authors.initials: Y
authors.lastname: Zhang
authors.forename: Abigail H
authors.initials: AH
authors.lastname: Conrad
authors.forename: Rudy
authors.initials: R
authors.lastname: Thoma
authors.forename: Gary W
authors.initials: GW
authors.lastname: Conrad
mesh_terms: D006801:Humans; D007536:Isomerism; D015394:Molecular Structure; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization; D013970:Thyronines / Q000032:analysis* / Q000097:blood / Q000737:chemistry*
chemical_list: D013970:Thyronines; C013068:3-monoiodothyronine