Table 1.

Single-epitope sandwich assay validation.

Limit of detection0.4 ng/L (determined for BNP form)
Linearity range0.00023–17.6 nmol/L (antigens: BNP, proBNPs; r2 = 0.999)
Within-assay imprecision (CV), %
 Low concentration2.3 (proBNP, 30 ng/L), 7.2 (BNP, 10 ng/L)
 Medium concentration3.7 (proBNP, 300 ng/L), 3.7 (BNP, 100 ng/L)
 High concentration5.4 (proBNP, 3000 ng/L), 5.0 (BNP, 1000 ng/L)
Total imprecision (CV), %
 Low concentration9.2 (proBNP, 100 ng/L)
 Medium concentration9.0 (proBNP, 1000 ng/L)
 High concentration9.2 (proBNP, 10 000 ng/L)
Recovery, %
 Low concentration101.7,1 98.52 (proBNP, 100 ng/L)
 Medium concentration99.8,1 100.32 (proBNP, 1000 ng/L)
 High concentration93.4,1 94.12 (proBNP, 10 000 ng/L)
Cross-reactivity
 ANP3 (1000 ng/L)BNP value, 0.13 ng/L
 CNP (1000 ng/L)BNP value , 0.00 ng/L