Development of a High Sensitivity Quantitative SPE-LC/MS/MS Assay for Bradykinin in Human Plasma Using ionKey/MS Technology

摘要

IonKey/MS provided a 10X increase in assay sensitivity and 7X improvement in S:N over the 2.1 mm ID scale. SPE using mixed-mode SPE reduces matrix interferences, enhances selectivity, and minimizes peptide loss. The ionKey/MS method is linear from 2.5-8,000 pg/mL, with no carry-over. QC samples at all levels easily met recommended FDA regulatory criteria with mean accuracies ranging from 92.7-104.0 and mean %CV's of 1.2-4.31, indicating an accurate, precise and reproducible method. A highly sensitive ionKey/MS method was developed that could distinguish a change of 2.5 pg/mL of bradykinin over the endogenous level.