Patent Document ID: 20110319295
Application ID: 13102669
Patent Flag: 0

Claim One:
1. A method for simultaneously determining the level of and/or phosphorylation state of at least one target protein or peptide in a single sample, comprising: (a) adding at least one internal standard protein or peptide corresponding to each target protein to the sample; (b) reducing and alkylating the at least one target protein or peptide in the sample without the use of urea; (c) digesting the at least one target protein and the at least one internal standard protein or peptide by contacting the sample with at least one protease; (d) analyzing the fragments of said digesting by a mass spectrometry-based method; and (e) determining the level of and/or phosphorylation state of the at least one target protein or peptide using the results of the analysis of the fragments.