Simultaneous Mass Spectrometric quantification of multiple p‐tau species in plasma – findings along the Alzheimer´s disease continuum

Blood phosphorylated tau (p‐tau) species at positions 181, 217 and 231 have been demonstrated accurate biomarkers of Alzheimer´s disease pathology. Comparisons to assess the performance of each phosphorylation along the Alzheimer´s disease (AD) continuum rely on the use of different immunoassays. In the current study, we simultaneously quantified the plasma concentration of six different phosphorylated (p‐tau 181, 199, 202, 205, 217 and 231), and two non‐phosphorylated, tau peptides using a targeted Mass Spectrometric (MS) method.