The determination of salivary oxypurines before and after exercise by combined liquid chromatography-field asymmetric waveform ion mobility spectrometry-time-of-flight mass spectrometry
journal contributionposted on 15.06.2018, 12:44 by Kayleigh L. Arthur, Lynsey S. Wilson, Matthew Turner, Martin Lindley, Jim Reynolds, Colin Creaser
© 2018 Springer-Verlag GmbH Germany, part of Springer Nature A method combining field asymmetric waveform ion mobility spectrometry with liquid chromatography-mass spectrometry (LC-FAIMS-MS) has been developed for the analysis of the oxypurine compounds hypoxanthine (HX) and xanthine (XA) in saliva. Separation of the oxypurines from interfering matrix components was investigated using FAIMS-MS. The selected FAIMS parameters were then applied to the rapid LC-FAIMS-MS analysis of HX and XA using a short chromatographic separation method (7 min). A comparison of the LC-MS method with and without FAIMS applied, resulted in improved discrimination from saliva matrix interferences and improved chromatographic peak integration for both HX and XA using a FAIMS separation. A quantitative evaluation of the LC-FAIMS-MS method was performed giving limits of detection of 2.0 ng mL −1 for HX and 1.8 ng mL −1 for XA, and limits of quantification of 6.6 ng mL −1 for HX and 6.0 ng mL −1 for XA. The developed LC-FAIMS-MS method was applied to the targeted analysis of the oxypurine metabolites in saliva collected from healthy male athletes (n = 11) before and after exercise designed to induce oxidative stress; post-exercise collection time-points included immediately after exercise, one hour and twenty-four hours’ post-exercise. The salivary concentrations of both HX and XA were lower after physical exercise, compared to the pre-exercise (rest) concentrations and returned to approximately pre-exercise levels after twenty-four hours. The method reported has the potential for monitoring the salivary oxypurines, HX and XA, as biomarkers of oxidative stress and in other clinical applications.
This work was supported by Owlstone Ltd. and Loughborough University.
- Sport, Exercise and Health Sciences