Tryptic Peptides

The need for absolute quantitation of protein expression levels in biological samples is of major importance in proteomics. The simplest and most cost-effective method of protein quantification involves the use of peptides containing amino acids incorporating heavy stable isotopes.
By using stable-labelled versions of tryptic peptides as internal standards, it is possible to directly quantify protein levels in a digested sample via mass spectrometry.
We supply heavy and light versions of common tryptic peptides ready to use in 1x 25 nmol tubes as detailed below:
If your desired tryptic peptide is not listed please refer to our custom synthesis page and request a custom peptide synthesis quotation.