Radioactive Isotope Labeling
I-125 labeled peptides for radioimmunoassay and ligand binding studies.
Veya Peptide prepares radiolabeled peptides for receptor-binding, pharmacokinetic, and autoradiography studies. Radiolabeling delivers the sensitivity that binding assays and trace-level ADME work require, with ¹²⁵I, ³H, and ¹⁴C the most common choices.
Radioiodination and tritiation are performed under appropriate licensing and handling controls. We match isotope, labeling chemistry, and specific activity to your assay, and advise on decay, storage, and shipping logistics.
Radioiodination (¹²⁵I)
Iodine-125 gives very high specific activity and is the workhorse for receptor-binding assays. We select the method that preserves your peptide's activity.
- Chloramine-T / IODO-GEN — direct oxidative iodination of tyrosine or histidine residues.
- Bolton–Hunter — conjugation labeling when direct iodination would disrupt activity.
- Purification — HPLC separation of mono-iodinated product from unlabeled and di-iodinated species.
Tritiation (³H) & ¹⁴C
For metabolic-stability and long-duration studies, tritium and carbon-14 provide stable, uniformly-incorporated labels.
- Tritium (³H) — high specific activity with a long half-life, ideal for ADME and metabolism studies.
- Carbon-14 (¹⁴C) — backbone-incorporated label for mass-balance and long-term tracing.
Applications & Logistics
Radiolabeled peptides underpin classic quantitative pharmacology. We support the practical side too.
- Receptor binding — saturation (Kd/Bmax) and competition (Ki) assays.
- Autoradiography — tissue-section receptor localization.
- Shipping — decay-corrected activity, handling data sheets, and compliant transport.
Service Specifications
| Parameter | Specification |
|---|---|
| Isotopes | ¹²⁵I · ³H · ¹⁴C |
| Iodination | Chloramine-T · IODO-GEN · Bolton–Hunter |
| Purification | HPLC (mono-iodinated isolation) |
| Applications | Receptor binding · ADME · autoradiography |
| Handling | Licensed facility; compliant shipping |
| Deliverable | Labeled peptide + specific-activity & decay data |
Frequently Asked Questions
Which isotope should I use?
¹²⁵I gives the highest sensitivity for receptor-binding assays. Choose ³H or ¹⁴C for metabolic-stability and mass-balance work where a longer half-life and backbone label matter.
Will iodination affect binding?
It can if a tyrosine sits in the binding region. In that case we use Bolton–Hunter conjugation labeling to preserve activity.
How is specific activity reported?
We provide decay-corrected specific activity at a reference date along with handling and storage guidance for safe use.
Request Radiolabeling
Tell us your peptide, preferred isotope, and assay, and our scientists will recommend the labeling chemistry and confirm feasibility. Contact our team to discuss your study.