Patent ID: 9274124
Filing Date: 2016-03-01
CPC Classification: C07K,C12Y,G01N

Claim Text:
1. A carrier stable isotope standard (carrierSIS) complex comprising: a carrier having at least one carrier linkage site and at least one extended stable isotope standard (SIS) peptide having a peptide linkage site, wherein said SIS peptide is isotope labeled in one or more amino acids of said peptide; wherein said carrier and said peptide are bound through a covalent linkage between said peptide linkage site and said carrier linkage site, wherein the linkage between said carrier linkage site and said peptide linkage site is not a proteolytic enzyme cleavage site, wherein said SIS peptide can be liberated from said carrier by action of a proteolytic process yielding at least one free SIS peptide that is chemically identical to the natural peptide for which said SIS peptide is a standard except for said isotope labeling, and wherein more than 90% of the SIS peptides bound to said carrier have the correct sequence compared to the natural peptide for which said SIS peptides are a standard.