Multiple reaction monitoring (MRM)/parallel reaction monitoring (PRM)
Multiple reaction monitoring (MRM) or parallel reaction monitoring (PRM) provides a targeted proteomics approach incorporating relative or absolute quantification. By using LC MS to focus on the specific properties (LC retention time, parent mass and daughter ion masses) of peptides that are unique to the protein of interest. Unique peptides for the target protein are identified from in silico proteolytic digest of the sequence and from databases of experimental data. Synthetic forms of the peptides are prepared and used to establish the LC and mass spectrometric parameters (limit of detection, limit of quantitation, dynamic range) for quantification of the protein in biological samples.