For Research Use Only. This product is supplied exclusively for laboratory research and is not intended for human or veterinary use.
IGF-1 LR3 Research Peptide
Long R3 IGF-I (IGF-1 LR3) is an 83-amino-acid analogue of insulin-like growth factor I. It contains an N-terminal extension and an arginine substitution at position 3, modifications developed to reduce binding to IGF-binding proteins while retaining IGF-1-receptor activity.
The analogue was developed as a laboratory reagent and has been used extensively in cell-culture and receptor research. Findings from cells or animals should not be converted into claims about muscle growth, fat loss or human-use outcomes.
Technical Specifications
| Product | Long R3 IGF-I / IGF-1 LR3 |
|---|---|
| Peptide length | 83 amino acids |
| Parent molecule | Insulin-like growth factor I |
| Key modifications | 13-residue N-terminal extension and Arg substitution at position 3 |
| Molecular weight | Approximately 9111.6 g/mol |
| Research target | IGF-1 receptor signalling with markedly reduced IGF-binding-protein affinity |
| Purity | Above 99% by third-party HPLC testing |
| Physical form | Lyophilised research material |
| Available format | 1mg |
| Intended use | Laboratory research and analytical use only |
Independent Batch Testing
Every current ZENTRA IGF-1 LR3 batch is independently tested and records an HPLC purity result above 99%. Use the batch number printed on the product label to locate the corresponding third-party report in our Batch Verification and COA Centre. Researchers should consult the individual report for the exact analytical methods, result and testing date for their supplied batch.
IGF-1 LR3 Research Context
The original recombinant-analogue research showed that Long R3 IGF-I has substantially reduced affinity for IGF-binding proteins and enhanced biological potency in certain cell systems. It is also used as a defined supplement in serum-free mammalian cell culture.
It is not equivalent to endogenous IGF-I and should not be described as simply “long-acting IGF-1” without explaining the binding-protein and sequence modifications.
Storage and Handling
Keep unopened lyophilised material at approximately -20°C for long-term storage. Protect from light, moisture, adsorption and repeated temperature changes. Low-concentration protein solutions can be sensitive to container and buffer conditions, so use a validated laboratory method.
IGF-1 LR3 Research FAQs
What is IGF-1 LR3?
It is an 83-amino-acid engineered IGF-I analogue with an N-terminal extension and an Arg3 substitution.
How does it differ from native IGF-I?
Its modifications greatly reduce affinity for IGF-binding proteins while retaining activity at the IGF-1 receptor.
What is its molecular weight?
The commonly reported molecular weight is approximately 9111.6 g/mol.
Where is it used in research?
It is used in receptor, signalling and serum-free mammalian cell-culture studies.
How is purity verified?
The current batch is independently HPLC tested above 99% and linked to its online COA.
Is it intended for human use or bodybuilding?
No. It is supplied solely as a laboratory research reagent.
Selected Scientific Sources
- Novel recombinant IGF-I analogues and the importance of binding proteins.
- Long R3 IGF-I as an alternative growth factor in serum-free HEK293 culture.
- IGFBP-3 effects on IGF-I and Long R3 IGF-I signalling in myogenic cells.
Research Resources
- GH-Pathway Research Bundle
- CJC-1295 without DAC
- Ipamorelin Research Peptide
- Batch Verification and COAs
- Research Compound Storage Guide
- Browse All Research Peptides
For research use only. Not for human or veterinary use.






