IGF-1 LR3 (Long Arginine 3 IGF-1) is a synthetic 83-amino acid analog of human insulin-like growth factor 1 (IGF-1), modified by an arginine substitution at position 3 and a 13-amino acid N-terminal extension. It is a frequent subject of laboratory research and is supplied as a lyophilized powder for research use only.
In published in vitro and preclinical research, IGF-1 LR3 has been studied in connection with binding to the IGF-1 receptor (IGF-1R) and reduced affinity for IGF-binding proteins (IGFBPs), and with downstream signaling pathways including PI3K/Akt and MAPK/ERK. These studies are conducted in cell-culture and animal research models. The findings derive from laboratory research and do not describe or imply any effect, benefit, or use in humans or animals.
Published literature has examined IGF-1 LR3 across a range of cell-culture and animal research models relating to IGF-1R signal transduction biology, making it a frequently used research tool in IGF-1R-expressing cell lines. These reports reflect controlled laboratory conditions only and do not translate to dosing, treatment, or applications in any other context. Its mechanism is studied alongside related research compounds such as Follistatin, Tesamorelin, and CJC-1295.
For further reading, see published research on IGF-1 LR3 on PubMed.
Product Specifications
| CAS Number | 143045-27-6 |
| PubChem CID | 381123731 |
| Molecular Formula | C₄₀₀H₆₂₅N₁₁₁O₁₁₅S₉ |
| Molecular Weight | ~9,117.5 g/mol |
| Amino Acid Count | 83 |
| Synonyms | Long R3 IGF-1, LR3-IGF-1, Long-(Arg3)-IGF-1 |
| Purity | ≥99% by HPLC | COA available |
| Physical Form | Lyophilized powder |
| Storage Conditions | Store at −20°C; protect from light and moisture |
For Research Use Only. Not for use in diagnostic, therapeutic, or human or animal in-vivo procedures. This product is sold exclusively for in-vitro laboratory research use. It is not a drug, dietary supplement, food, or cosmetic and has not been approved by the U.S. Food and Drug Administration for any use. Not intended to diagnose, treat, cure, mitigate, or prevent any disease. Not for human or animal consumption.










Dr. K. Patel –
IGF-1 LR3 is exactly what I needed. Documentation is thorough, purity confirmed, and the concierge team helped me with my order. Excellent supplier.