Agilent LC/MS and LC systems demonstrates high sensitivity towards peptides and protein biomarkers
6 Oct 2020
In a recently published application note, Agilent Technologies demonstrates the quantitative sensitivity of 99 signature peptides from 75 protein biomarkers in plasma using the 6495 triple quadrupole LC/MS system and AJS ionization source.
In translational research, increased throughput and increased multiplexing mass spectrometry using multiple reaction monitoring (MRM)-based LC/MS methods have become increasingly popular for targeted, bottom-up quantification of protein biomarkers.
Researchers often target signature peptides from a limited number of proteins in large cohorts and monitor their expression levels during a specified time period, often leading to hundred or thousands of biological samples. In such large studies, high throughput, robustness, and reproducibility are essential when deploying LC/MS methods.
In this application note, Agilent highlight the quantitative performance of MRM-based LC/MS analysis of peptides derived from protein biomarkers in human plasma using the Agilent 1290 Infinity II LC system coupled to the Agilent 6495 triple quadrupole LC/MS with Jet Stream ionization source.
To assess overall quantitative performance for protein biomarker peptides, a commercially available mixture of stable isotope-labeled standard (SIS) peptides was spiked into human plasma digest at nine different concentrations. Standard curves of 99 SIS peptides were generated to determine their lower limit of quantification (LLOQ) in plasma matrix.
The results showed excellent analytical performance under standard flow conditions with the LC/TQ system for targeted peptide quantification in heavy matrix.