| 摘要 |
A method for quantitative measurement using mass spectroscopy of a peptide or peptides generated from one or multiple analyte proteins by enzymatic or chemical cleavage, the method comprising the step of exposing together the sample to be analysed and one or multiple mass-labelled peptide internal standard precursors to enzymatic or chemical cleavage so as to generate from said precursor one or multiple mass-labelled peptide internal standards, wherein the mass-labelled peptide internal standard precursor comprises an extension of a least one amino acid N-terminal to the N-terminus of the N-terminal-most mass-labelled peptide internal standard generated therefrom, and an extension of at least one amino acid C-terminal to the C-terminus of the C-terminal-most mass-labelled peptide internal standard generated therefrom. |
