Influence of Sampling and Storage Conditions on B-Type Natriuretic Peptide Immunoreactivity for 3 Automated Assays

摘要

B-Type natriuretic peptide (BNP) is a marker for diagnosis and prognosis of congestive heart failure (CHF). In response to the analytical uncertainties of automated BNP assays, the IFCC Committee on Standardization of Markers of Cardiac Damage published recommendations for the evaluation of in vitro BNP stability (1).We analyzed the effect of exposure to room temperature for 24 h on whole-blood BNP immunoreactivity or the effect of 1 freeze–thaw (FT) cycle on plasma BNP immunoreactivity in 3 different assays. Blood samples from 4 CHF patients were collected on ice with Sarstedt tubes containing potassium EDTA (1.6 mg/mL EDTA), EDTA with aprotinin (500 kallikrein-inhibitory units/mL), and EDTA with benzamidine (80 μmol/mL). Whole blood was split into 2 aliquots: one was centrifuged (2400 g for 10 min) for immediate assay (baseline), with the remaining plasma stored at ?20 °C; the other aliquot was allowed …