Determination of matrix effect within method validation is critical to determine if quantitation of a molecule will be impacted within a patient population. For mass spectrometry approaches suppression or enhancement of the analyte response is usually observed to be proportional to the change for the response of the stable label internal standard; therefore, quantitation or the accuracy of the quantitation of a sample is not impacted. Protein biomarker applications coupled with mass spectrometry generally utilize a unique peptide representative of the protein for quantitation in conjunction with a stable label peptide internal standard. This presentation will focus on the identification of differences in apparent matrix effects between healthy matrix and disease state matrix. Specifically we aim to address how we determine within protein biomarker applications if the unique peptide sequence representative of the intact molecule and the peptide internal standard are being impacted proportionally or disproportionally within healthy and disease state matrices and how a disproportional impact to response might impact the accuracy of reported concentrations.
Learning Objectives:
Understand the importance of the different approaches to matrix effect testing for protein biomarkers vs small molecule biomarkers.
Understanding the necessity of testing both healthy and disease state matrix in method development for protein biomarker analysis.
Understanding the impact of analyte to internal standard matrix effect ratio.
