Table 2.

Matrix effect recovery of the Aβ peptides using both normalization methods of Pittsburgh assays

PAβ V2.0 assay		Plasma, pg/mL	Matrix effect recovery with Aβ1–38 IS (%)	Matrix effect recovery with Aβ1–40 IS and Aβ1–42 IS (%)
Aβ1–40	Level 1	118.2	62.8	66.0
	Level 2	53.6	66.2	72.7
	Level 3	21.4	70.5	78.9
Aβ1–42	Level 1	47.2	57.8	63.4
	Level 2	23.0	62.3	76.9
	Level 3	10.8	69.8	85.4
PAβ V1.0 assay		Plasma, pg/mL	Matrix effect recovery with Aβ1–38 IS (%)	Matrix effect recovery with Aβ1–40 IS and Aβ1–42 IS (%)
Aβ1–40	Level 1	118.2	60.0	60.0
	Level 2	53.6	66.5	70.6
	Level 3	21.4	75.7	81.1
Aβ1–42	Level 1	47.2	55.8	62.0
	Level 2	23.0	65.2	78.9
	Level 3	10.8	74.5	89.1