Stable Isotope Labeling of Peptides

BOC Sciences has a professional team, state-of-the-art synthesis and purification technology, rigorous work ethic, and strict quality requirements to ensure that we can meet the different purity requirements of our customers for isotope labeling of peptides. With our business philosophy of customer first, BOC Sciences provides high-quality products from micrograms, milligrams to kilograms.

Fig.1 Synthesis of stable isotopically labeled peptides. (Tsai et al., 2017)

Stable Isotope Labeled Peptides

Stable isotope labeled peptides are distinguished from ordinary peptides by the substitution of C by ¹³C or N by ¹⁵N in one/several amino acids in their structure. As peptides are being used more and more widely and deeply in the biomedical field, the demand for labeled and modified peptides is increasing, and so is the demand for higher quality. Stable isotope labeling is a typical one of them. Stable isotope labeling tracers enable peptide metabolic pathway studies and are able to readily track changes in the position and quantity of isotope-labeled peptides containing them in vivo or in vitro.

Services for Stable Isotope Labeled Peptide

BOC Sciences offers several types of stable isotopes for labeling peptides, including ²H (deuterium), ¹³C and ¹⁵N. Our main preparation route is to directly introduce isotopically labeled amino acids into the peptide synthesis process in order to label the entire peptide chain.

Our commonly used isotope-labeled amino acids include the following:

• Tyrosine (Tyr)
• Threonine (Thr)
• Lysine (Lys)
• Arginine (Arg)
• Glutamic acid (Glu)

Types of stable isotope peptide synthesis:

• ¹⁵N labeled peptides
• ¹³C labeled peptide
• ¹⁵N and ¹³C double-labeled peptides
• ²H labeled peptides

Stable Isotope Peptide Synthesis

Before synthesizing stable isotope labeling of peptide, the amino acid sequence of the target peptide and the amino acid positions to be labeled need to be determined. And then, select the amino acid monomers with stable isotope labeling, such as ¹³C-labeled glutamic acid or arginine, or deuterated glycine. We can customize high-quality stable isotope-labeled amino acids for you. Next, using solid phase synthesis, the amino acid monomers are coupled one by one to the peptide chains on the synthetic resin. Among other things, the reactive groups of certain amino acid side chains may need to be protected. The target peptide is obtained only after deprotection is completed.

Identification of Stable Isotope Peptides

Isotope labeling tracer method has the advantages of high sensitivity, simple localization, and accurate quantification, which can be distinguished the isotope by measuring the molecular mass or centrifugation technique. It needs to be measured by mass spectrometer, gas chromatography, nuclear magnetic resonance and other mass analyzing instruments.

Scale-up Synthesis of Stable Isotope Peptides

Based on the results of small-scale peptide synthesis, the synthesis conditions and steps need to be optimized first to ensure high yield and quality peptide synthesis. Once the synthetic conditions have been optimized, scale-up synthesis can be performed to obtain sufficient quantities of stable isotope peptides. At the same time, various analyses and characterizations need to be performed to ensure reproducibility and batch consistency at the synthetic scale.

Advantages

• Excellent peptide synthesis and purification technology
• Stringent quality requirements for stable isotope labeled oeptide
• Quality assurance: HPLC chromatogram and Mass spec analysis
• Provide quality service at the microgram, milligram to kilogram level
• Meeting different purity requirements for isotope-labeled peptides

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