With the HRMS instrument, 23 out of the 90 selected model polyphenols were detected, while 37 analytes were detected with LRMS . From these analytes, 18 were detected in both platforms, with their concentrations around a factor 3 lower in HRMS than in LRMS (Table ). Thus, the 5 analytes that were detected with HRMS but not LRMS could be from the analyte having a better LOD in the HRMS, such as is the case for caffeic acid. Alternatively, it could be a false positive or interference with another analyte of the same MS 1 mass since in HRMS only a MS 1 scan was acquired and no fragmentation data. A difference in determined concentrations between HRMS and LRMS workflows is normal, e.g. up to a 20% difference was found for pesticides in various foodstuffs by del Mar Gómez-Ramos et al. . Though here the difference between the two workflows was a factor of 3, most likely due to human biofluids being more complex matrices than foodstuffs and having more interferences. Despite the factor difference here being larger than in previous research, the majority of the analytes are still detected, showing that HRMS is suitable for the qualitative and semi-quantitative analysis of polyphenols and their metabolites in human samples.