Reduced IGFBP binding
E3R + 13-aa extension lower IGFBP-3 affinity ~100x.
CAS: 143045-27-6
A long-acting analogue of insulin-like growth factor 1 engineered with reduced binding-protein affinity, used in research models of cell proliferation, protein synthesis, and IGF-1 receptor signaling.

Janoshik batch COA · independent verify link · USA warehouse shipping
E3R + 13-aa extension lower IGFBP-3 affinity ~100x.
~20–30 h in research models vs minutes for native IGF-1.
HPLC + MS verified per batch. CoA included.
IGF-1 LR3 is an 83-amino-acid analogue of human IGF-1 with two engineered changes: a 13-amino-acid N-terminal extension and substitution of glutamic acid at position 3 with arginine (the "R3" of the name). Vorix Labs supplies IGF-1 LR3 as a research catalog item with Janoshik Analytical batch CoA documentation and USA warehouse fulfillment. Laboratory / in-vitro use only — not for human or veterinary use.
IGF-1 LR3 is an 83-amino-acid analogue of human IGF-1 with two engineered changes: a 13-amino-acid N-terminal extension and substitution of glutamic acid at position 3 with arginine (the "R3" of the name). These modifications reduce binding to insulin-like growth factor binding proteins (especially IGFBP-3) roughly 100-fold versus native IGF-1, which extends circulating half-life in research models from minutes to approximately 20–30 hours. Signaling at the IGF-1 receptor (PI3K/Akt and MAPK pathways) is preserved.
IGF-1 LR3 is a long-R3 IGF-1 analog frequently ordered for cell-culture and receptor studies. Targets “buy IGF-1 LR3 research peptide” with CoA-backed USA stock.
Straight answers for researchers comparing purity, CoA documentation, kits, and shipping.
Yes. IGF-1 LR3 from Vorix Labs is sold strictly for laboratory / in vitro research. It is not for human or veterinary use and is not evaluated by the U.S. FDA for any clinical purpose.
Every Vorix batch is identity-verified with a Janoshik Analytical Certificate of Analysis (CoA). CoA access is available on the product page and through our CoA library for researchers who need batch documentation.
Yes. Most catalog SKUs offer a single vial and a kit-of-10 option with kit pricing when inventory supports a full kit. Select the package size on the product page before adding to cart.
Orders ship from our USA warehouse with domestic fulfillment. Standard shipping is free on qualifying orders of $250+.
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Not for human consumption. This product is sold exclusively for research and educational purposes. It is not intended to diagnose, treat, cure, or prevent any disease.
By purchasing this product, you confirm that you are a qualified researcher and will use it in accordance with all applicable laws and regulations.