MASS SPECTROMETRY BIOMARKER ASSAY.

摘要

The invention provides a method for determining the presence of one or more polypeptide biomarkers in a sample, comprising the steps of: (a) subjecting the sample to a mass spectrometric (MS) analysis and recording retention time index and corresponding mass for each signal detected; (b) con-elating the mass corresponding to each signal to a reference database of biomarker masses to form a con-elation between each signal and a reference biomarker, and discarding those signals whose masses do not correlate to a reference boimarker mass; (c) storing those signals whose masses correlate with a reference biomarker; (d) confirming the con-elation between each stored signal and a reference biomarker by matching the MS spectrum of each signal with the MS spectrum of the reference biomarker in the database using a similarity measure, to define a set of positively correlating signals; (d) measuring the intensity of each positivley coreelating signal and scoring its absolute signal intensity or its relative signal intensity using a discrimination function; (e) applying a threshold to the score values obtained from the discrimination function to detemiine the presence or absence of the biomarker.