title: Liquid Chromatography-Tandem Mass Spectrometry Method for Determination of Homocysteine in Rat Plasma: Application to the Study of a Rat Model for Tauopathies.
abstract: Hyperhomocysteinemia is a common occurrence in many neurodegenerative diseases, including tauopathies. We developed and validated a simple and sensitive liquid chromatography-tandem mass spectrometry method for the analysis of homocysteine (Hcy) in rat plasma. Hcy was analyzed using ultra-performance liquid chromatography on a C8 column with detection by positive ESI tandem mass spectrometry. For optimal retention and separation, we used ion-pair reagent-heptafluorobutyric acid. The method utilizes heavy labeled internal standard and does not require any derivatization or extraction step. The procedure was validated in compliance with the European Medicines Agency guideline. The limit of detection was 0.15 µmol/L and the limit of quantification was 0.5 µmol/L. The method showed excellent linearity with regression coefficients higher than 0.99. The accuracy was in the range of 93-98%. The inter-day precision (n = 5 days), expressed as % relative standard deviation, was in the range 3-8%. Using this method, we analyzed plasma samples from two transgenic lines of the rat model for tauopathies.
authors.affiliation: Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava 84510, Slovak Republic AXON Neuroscience SE, Dvorakovo nabrezie 10, Bratislava 81102, Slovak Republic andrej.kovac@savba.sk.
authors.forename: Andrej
authors.initials: A
authors.lastname: Kovac
authors.affiliation: AXON Neuroscience SE, Dvorakovo nabrezie 10, Bratislava 81102, Slovak Republic Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5/A14, Brno 62500, Czech Republic.
authors.forename: Katarina
authors.initials: K
authors.lastname: Svihlova
authors.affiliation: Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava 84510, Slovak Republic AXON Neuroscience SE, Dvorakovo nabrezie 10, Bratislava 81102, Slovak Republic.
authors.forename: Alena
authors.initials: A
authors.lastname: Michalicova
authors.affiliation: Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava 84510, Slovak Republic AXON Neuroscience SE, Dvorakovo nabrezie 10, Bratislava 81102, Slovak Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Novak
mesh_terms: D000818:Animals; D016022:Case-Control Studies; D002853:Chromatography, Liquid / Q000379:methods*; D004355:Drug Stability; D006710:Homocysteine / Q000097:blood*; D057230:Limit of Detection; D016014:Linear Models; D051381:Rats; D011918:Rats, Inbred SHR; D055647:Rats, Transgenic; D017208:Rats, Wistar; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry / Q000379:methods*; D024801:Tauopathies / Q000097:blood*
chemical_list: D006710:Homocysteine