摘要 |
The present invention is related to a method for preparing an internal peptide standard, comprising a) providing a first tag, and b) coupling of a first peptide to the first tag, whereby the first peptide comprises an amino acid sequence, or a) providing a first tag and b) coupling to the first tag the amino acids forming the first peptide comprising an amino acid sequence, whereby the C-terminal end of the amino acid sequence of the first peptide corresponds to the C-terminal end generated by a sequence-specific hydrolysis of an amide bond, ester bond or thioester bond preferably of an amide bond of a peptide. |