Towards clinical implementation: Establishing standardized operating procedures to limit the pre‐analytical sample handling effects on the novel Alzheimer’s disease blood‐based biomarkers

Background Clinical implementation of novel blood-based biomarkers for Alzheimer’s disease (AD) will aid in accurate, less-invasive diagnosis. However, variation blood handling may affect the accuracy biomarker’s measurement. Establishing standardized operating procedures (SOPs) to mitigate these effects is essential implementing into clinical use. We aim provide an evidence-based SOP specific AD by studying multiple pre-analytical variations samples from and healthy controls (HCs). Here, we show first results obtained, addressing effect adsorption lab plastics, during sample processing. Method Blood are being withdrawn 150 volunteers (AD HCs) treated according one ten experimental protocols. Several aliquots per be shared analyzed among labs, focusing on labs with P-tau plasma tests. Preliminary acquired 1x, 2x 4x tube transfers fresh polypropylene tubes pipet tips at every transfer, compared no as a reference condition. Sample analysis was performed Simoa using neurology 4-plex E assay (Aβ1-42, Aβ1-40, GFAP, NfL), P-tau181 V2 assay. A median value measured least 10% condition regarded significant change. Result Formally, medians all NfL Ptau-181), stayed within predefined range, both HC. levels Aβ1-42 Aβ1-40 showed obvious tendency decrease 4th transfer. For HCs were more affected those (median 92%; AD: = 95%). Aβ1-42, similar (median: 91% 93%). This not so apparent Aβ1-42/Aβ1-40 ratio. Conclusion In line results, 4 or less should have influence biomarkers. Aβ peptide measurements, ratio appears stabilize