STABLE ISOTOPE LABELED (SIL) PEPTIDES

Peptides labeled with stable, non-radioactive isotopes are increasingly used for convenient detection in research. Isotope–labeled, or ‘heavy’ amino acids, are derived from natural amino acids by substitution of certain atoms (N, C, H) with their ‘heavy isotope’ variant. The most frequently used stable isotopes are 13C (carbon-13), 15N (nitrogen-15), and 2H (deuterium).

SIL-peptides display identical physiochemical properties and chemical reactivity as their non-labeled counterparts (apart from a few exceptions). However, under certain conditions labeled and unlabeled peptides behave differently. This constitutes the basis for using SIL-peptides in a variety of absolute quantification applications such as quantitative proteomics, the quantification of complex protein mixture at very low concentration, or NMR studies.

Pepscan has produced thousands of such custom ‘heavy’ peptides. Pepscan and Buchem established a supply alliance for the highly enriched stable amino acids from premium manufacturer Cambridge Isotope Laboratories (CIL). The uniformly labelled amino acids used for the Fmoc-based solid-phase peptide-synthesis all have over 99% isotopic purity.

These important attributes have enabled us to successfully respond to the ever changing demand for high quality SIL-compounds. All stable isotope labeled peptides undergo mass spectrometric analysis and stringent analytical HPLC to establish the final purity, and to assure that our customers receive only the highest quality peptides for absolute quantitation.

Please do not hesitate to contact us for your request.