FIGURE 3.

Custom sample diluent reduces bead clumping and artifact signal. A panel of four samples (3 Alzheimer's disease [AD] serum samples and calibrant peptide) were measured in three‐step p217+tau assay after 1:2 dilution in a panel of sample diluents. The diluents varied in (a) base buffer, (b) salt concentration, and (c) presence of heterophilic blocker (HBR9). The diluent impact on (A) bead count and (B) signal was measured, revealing that all custom buffers rescued the low bead count and outlier high signal seen with Simoa homebrew buffer in serum. The ideal diluents were Tris based with HBR9 included. AEB = signal