P4-187: comparison of measured plasma biomarkers of alzheimer's disease and parkinson's disease between edta k2 and edta k3 blood collecting tubes via immunomagnetic reduction

In clinical practice, there are several types of ethylenediaminetetraacetic-acid (EDTA) blood collecting tunes in use. The popular tubes might be EDTA K2, which is spray-dried to the walls of the tube, and EDTA K3, which has liquid form of EDTA. Rare reports show the possible differences in the measured plasma biomarkers of Alzheimer's disease (AD) and Parkinson's disease (PD) between these types of tubes. In this work, these two types of tubes were used to collecting whole blood of a same cohort, followed by standardized processes for plasma preparation. In the cohort, there are 8 normal controls, 30 AD patients and 7 subjects with typical or atypical Parkinsonism. Plasma Aβ1-40, Aβ1-42, T-Tau and α-synuclein were assayed with immunomagnetic reduction kits. Through T-Test analysis, there is no significant difference in measured concentration between K2 and K3 for any of these biomarkers. The results show the linear relationships for the measured biomarker concentrations between K2 and K3 tubes (Aβ1-40: K2 = 0.9338K3 + 1.9763; Aβ1-42: K2 = 0.8676K3 + 2.5409; T-Tau: K2 = 0.7071K3 + 8.3054; α-synuclein: K2 = 0.7997K3 + 23.592).