Patent ID: 7632686

Claim:
A method of quantifying an amount of at least a first monitor peptide and a second monitor peptide in a biological sample, comprising: contacting the sample with (i) a first anti-peptide antibody specific for said first peptide and; (ii) a known quantity of a labeled version of said first peptide; contacting the sample with (i) a second antipeptide antibody specific for said second peptide, wherein said second antibody is different from said first antibody and; (ii) a known quantity of a labeled version of said second peptide, separating peptides bound by said first and said second antibodies from unbound peptides; eluting said peptides bound by said first and said second antibodies from said antibodies; measuring the amount of said first peptide eluted from said first antibody using a mass spectrometer; measuring the amount of said labeled version of said first peptide eluted from said first antibody using a mass spectrometer; calculating the amount of the first peptide in the biological sample; measuring the amount of said second peptide eluted from said second antibody using a mass spectrometer; measuring the amount of the labeled version of the second peptide eluted from said second antibody using a mass spectrometer; and calculating the amount of the second peptide in the biological sample, wherein said biological sample is a proteolytic digest of a bodily fluid sample.