What is the CAS number for IGF-LR3?

The CAS number for IGF-LR3 is 946870-92-4. Its molecular formula is C₄₀₀H₆₂₅N₁₁₁O₁₁₅S₉ (MW ~9,117 Da).

What doses of IGF-LR3 are available wholesale?

Wholesale Peptide Supply stocks IGF-LR3 in 1mg. Wholesale pricing is provided by quote based on order volume across 100–1,000 vials.

Is IGF-LR3 third-party tested?

Yes. Every lot of IGF-LR3 is tested by an independent third-party laboratory using HPLC/MS, and a per-lot Certificate of Analysis documenting identity and purity is available as a paid add-on.

Is IGF-LR3 for human use?

No. IGF-LR3 is sold strictly as a chemical reagent for in-vitro laboratory research and is not for human or veterinary use. Wholesale Peptide Supply is not a pharmacy or compounding facility.

How do I get wholesale pricing for IGF-LR3?

Request a quote through our contact form or open a wholesale account. An account manager replies with volume pricing and lead times, typically within 10 minutes during business hours.

Can I order IGF-LR3 in bulk?

Yes. IGF-LR3 is available for bulk and wholesale orders, quoted by dose and volume, with the lower price earned per compound at 100 kits (1,000 vials). Submit the doses and quantities you need for a bulk quote; all material is sourced in the USA and third-party HPLC/MS tested.

Why is IGF-LR3 handled differently from other peptides?

At approximately 9,117 Da it is a small protein rather than a short peptide, so it is more conformationally fragile. Laboratory practice conventionally uses a dilute acidic diluent rather than plain water, gentle swirling instead of vortexing, and aliquoting before freezing to avoid repeated freeze-thaw cycles. It is supplied for research use only.

What does the 'Long Arg3' in IGF-LR3 refer to?

It describes the two modifications to native IGF-1: 'Long' is the 13-residue N-terminal extension, and 'Arg3' is the arginine substitution at position 3. Together they substantially reduce IGF binding protein association, which is why the analog is used to study IGF-1 receptor signaling without the confound of binding-protein sequestration.

Research Use Only. IGF-LR3 is sold as a chemical reagent for in-vitro laboratory research. It is not a drug, supplement, or compounded preparation, and it is not for human or veterinary use. Wholesale Peptide Supply is not a pharmacy or compounding facility under 503A or 503B.

Growth HormoneCAS 946870-92-4

Wholesale IGF-LR3 — Bulk Research Supply

Buy IGF-LR3 wholesale and in bulk from a US-based research peptide supplier. Every lot is sourced in the USA and third-party third-party tested via HPLC/MS. Bulk IGF-LR3 is quoted by dose and volume from a 100-vial mix-and-match minimum; volume pricing is earned per compound at 100 kits.

IGF-LR3 (Long Arg3 IGF-1) is a synthetic IGF-1 analog with reduced IGFBP binding and significantly extended half-life, used to investigate IGF-1 receptor-mediated signaling and metabolic regulation.

Wholesale Catalog

Available Doses

Published per-vial wholesale pricing for IGF-LR3. Sold in kits of 10 vials with a 100-vial order minimum you can mix and match across compounds; volume pricing applies at 1,000+ vials. Contact us for larger or custom-volume quotes — typically answered within 10 minutes during business hours.

IGF-LR3 1mg

WPSIG1 · CAS 946870-92-4 · Growth Hormone

$30.19/vial · under 100 kits · $24.15/vial · 100+ kits of this item

Sold in kits of 10 vials · 100-vial order minimum (mix & match across compounds) · 100+ kits of this item unlocks the lower price

Quantity

10 vials

1 kit

Request a custom quote

Overview

IGF-LR3 (Long Arg3 IGF-1) is a synthetic IGF-1 analog with reduced IGFBP binding and significantly extended half-life, used to investigate IGF-1 receptor-mediated signaling and metabolic regulation.

History

Developed in the 1990s; the N-terminal extension and Arg3 substitution synergistically reduce IGFBP binding while maintaining receptor affinity.

Structure and mechanism

IGF-LR3 (Long Arg3 IGF-1) is a 83-residue analog of insulin-like growth factor 1 carrying two deliberate changes: a 13-residue N-terminal extension and an arginine substitution at position 3. The two work together. The Arg3 substitution sharply reduces affinity for the IGF binding proteins that sequester native IGF-1 in circulation, while the N-terminal extension further limits IGFBP association — so a much larger fraction of the molecule remains unbound and available to engage the receptor.

In laboratory models that property makes it a practical probe of IGF-1 receptor activation and the PI3K/Akt/mTOR cascade downstream of it, and of proliferation and survival endpoints in cell culture where native IGF-1's binding-protein interactions would otherwise confound the readout. At approximately 9,117 Da it is the largest molecule in this group by a wide margin — closer to a small protein than a peptide.

Reconstitution and handling (research use)

IGF-LR3 requires more care than the small peptides in the catalog. As a ~9 kDa protein it is the most conformationally fragile item here: it is conventionally reconstituted in a dilute acidic diluent rather than plain water, because solubility and stability are markedly better below neutral pH, and it should be swirled gently — never vortexed — to avoid denaturation at the air-liquid interface.

Lyophilized material is held at -20°C or colder and protected from light. Reconstituted solution is refrigerated at 2–8°C, and aliquoting before any freezing is strongly preferable, since repeated freeze-thaw cycles cause measurable activity loss in proteins of this size. Carrier protein is sometimes added for dilute working stocks to limit adsorption to labware. These notes describe general laboratory handling of a chemical reagent only — not human or veterinary use.

Wholesale sourcing notes

IGF-LR3 is stocked wholesale in a 1 mg presentation — a smaller fill than the peptide lines, which is standard for a recombinant protein of this molecular weight where working concentrations are far lower. Every lot is US-sourced and third-party verified by HPLC/MS for identity, purity, and quantitation, with a per-lot COA available as a paid add-on.

The 1 mg vial still counts toward the 100-vial mix-and-match minimum, so it can be added to an order built primarily from other compounds. Volume pricing spans the 100, 250, 500, and 1,000-vial bands.

Certificates of Analysis

Every lot of IGF-LR3 is tested by an independent third-party laboratory using HPLC/MS. 1 certificate is on file below — open any one to read the full report.

Lot	Dose	Tested	Certificate
100057-0603	1mg	2026-08-05

Key Areas of Research

IGF-1 receptor activation
PI3K/Akt/mTOR cascades
Cellular proliferation and survival

References

Clemmons D.R. (2007). Nat Rev Drug Discov 6(10):821–833.
Rinderknecht E., Humbel R.E. (1978). J Biol Chem 253(8):2769–2776.

IGF-LR3 — Frequently Asked Questions

What is IGF-LR3?: IGF-LR3 (Long Arg3 IGF-1) is a synthetic IGF-1 analog with reduced IGFBP binding and significantly extended half-life, used to investigate IGF-1 receptor-mediated signaling and metabolic regulation.
What is the CAS number for IGF-LR3?: The CAS number for IGF-LR3 is 946870-92-4. Its molecular formula is C₄₀₀H₆₂₅N₁₁₁O₁₁₅S₉ (MW ~9,117 Da).
What doses of IGF-LR3 are available wholesale?: Wholesale Peptide Supply stocks IGF-LR3 in 1mg. Wholesale pricing is provided by quote based on order volume across 100–1,000 vials.
Is IGF-LR3 third-party tested?: Yes. Every lot of IGF-LR3 is tested by an independent third-party laboratory using HPLC/MS, and a per-lot Certificate of Analysis documenting identity and purity is available as a paid add-on.
Is IGF-LR3 for human use?: No. IGF-LR3 is sold strictly as a chemical reagent for in-vitro laboratory research and is not for human or veterinary use. Wholesale Peptide Supply is not a pharmacy or compounding facility.
How do I get wholesale pricing for IGF-LR3?: Request a quote through our contact form or open a wholesale account. An account manager replies with volume pricing and lead times, typically within 10 minutes during business hours.
Can I order IGF-LR3 in bulk?: Yes. IGF-LR3 is available for bulk and wholesale orders, quoted by dose and volume, with the lower price earned per compound at 100 kits (1,000 vials). Submit the doses and quantities you need for a bulk quote; all material is sourced in the USA and third-party HPLC/MS tested.
Why is IGF-LR3 handled differently from other peptides?: At approximately 9,117 Da it is a small protein rather than a short peptide, so it is more conformationally fragile. Laboratory practice conventionally uses a dilute acidic diluent rather than plain water, gentle swirling instead of vortexing, and aliquoting before freezing to avoid repeated freeze-thaw cycles. It is supplied for research use only.
What does the 'Long Arg3' in IGF-LR3 refer to?: It describes the two modifications to native IGF-1: 'Long' is the 13-residue N-terminal extension, and 'Arg3' is the arginine substitution at position 3. Together they substantially reduce IGF binding protein association, which is why the analog is used to study IGF-1 receptor signaling without the confound of binding-protein sequestration.

Research Use Only

All products are intended solely for laboratory research purposes and are not for human or animal consumption. Must be handled by qualified professionals.