Protein biomarker quantification by mass spectrometry.

The protein biomarker field is becoming increasingly interested in multiple reaction monitoring mass spectrometry (MRM-MS) assays for biomarker tests. Originally developed years ago and used extensively to quantify small molecules, this technique is now being adapted to peptides. A summary is presented of MRM-MS techniques for quantification of protein biomarkers, including biomarker panels, and clinical applications of this approach. A survey of the current literature relating to the use of MRM-MS to quantify protein biomarker panels was conducted. Future directions for MRM-MS include qualification and verification of candidate protein biomarkers. Furthermore, the analytical characteristics of the MRM-MS approach make it ideally suited for the clinical laboratory as an assay for biomarker tests.