Introduction
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 substitutions are 12C by 13C (carbon-13), 14N by 15N (nitrogen-15), and 1H by 2H (deuterium).
Stable-isotope-labeled (SIL) peptides display identical physiochemical properties and chemical reactivity as their non-labeled counterparts (apart from a few exceptions). However, under certain conditions the minute mass difference make labeled and unlabeled peptides behave differently. This constitutes the basis for using stable isotope labeling 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.
At Kirkland Peptide, we have produced thousands of such custom ‘heavy’ peptides. These SIL-peptides are synthesized using only the highly enriched stable amino acids from premium supplier Cambridge Isotope Laboratories (CIL) for the Fmoc-based solid-phase peptide-synthesis in our laboratory. These uniformly labeled amino acids all have over 99% isotopic purity.
STABLE ISOTOPE OPTIONS
With more than 10 years of experience, and as a world-leading peptide manufacturing organization, Kirkland Peptide can provide customized peptides labeled with stable isotopes including 2H, 15N & 13C, respectively, or a combination of 15N & 13C. Even when the peptides are attached with specific modification motifs.
- 2H(deuterium)
- 15N
- 13C
- 15N and 13C combinations
Below lists is the most common stable isotopically labeled amino acids that can be used for the synthesis of peptides with stable isotopes containing carbon 13 (13C), Nitrogen 15 (15N).
