What is IGF-1 LR3?

Overview

IGF-1 LR3 is Long-R3 Insulin-like Growth Factor 1 — a 70-amino-acid analog with the third amino acid replaced by arginine and a 13-residue extension at the N-terminus. Those two modifications produce an IGF-1 that resists binding to IGFBPs (the carrier proteins that sequester native IGF-1) and therefore retains free-ligand activity for a markedly longer window. Why the modified form matters: Native IGF-1’s plasma half-life is ~10 minutes because IGFBPs bind and neutralize it almost instantly. LR3 stays active for 20+ hours, producing sustained IGF-1 receptor signaling that lets researchers study anabolic effects at physiologically relevant concentrations. IF the research endpoint involves sustained IGF-1 receptor activation — muscle protein synthesis, myogenic differentiation, or cartilage repair — THEN LR3 is the analog with the cleanest pharmacology. SO it belongs in protocols where free-ligand availability is the variable under test. ≥99% HPLC purity, CoA per batch.

Research areas

• IGFBP resistance

  <p>The Arg3 substitution disrupts IGFBP binding; the N-terminal extension slows proteolytic clearance. Together they produce a plasma half-life of 20+ hours.</p>

• Anabolic signaling

  <p>Sustained IGF-1R activation drives PI3K/Akt pathway output, mTOR-mediated protein synthesis, and myogenic differentiation in skeletal muscle models.</p>

• Research applications

  <p>Widely used in cell culture and in-vivo models of muscle hypertrophy, tissue repair, and insulin sensitivity — where native IGF-1&#8217;s short half-life is a confound.</p>

• Storage

  <p>Highly sensitive to freeze-thaw. Store lyophilized at -20°C; once reconstituted, refrigerate and use within 14 days.</p>

Storage & handling

Lyophilized IGF-1 LR3is stored at –20 °C protected from light. Once reconstituted with bacteriostatic water, store at 2–8 °C and use within 30 days for maximum stability.

Frequently asked questions

What is IGF-1 LR3?

IGF-1 LR3 (IGF-1 LR3) is a research compound studied in the area of healing & regeneration. A long-acting IGF-1 analog with Arg3 substitution. Studied for its sustained anabolic signaling without IGFBP sequestration.

What is the CAS number of IGF-1 LR3?

The CAS registry number of IGF-1 LR3 is 143045-27-6.

How should IGF-1 LR3 be stored?

Lyophilized IGF-1 LR3 should be stored at –20 °C protected from light. Once reconstituted with bacteriostatic water, store at 2–8 °C and use within 30 days for maximum stability.

How is the purity of IGF-1 LR3 verified?

Every Woosh Labs batch of IGF-1 LR3 is independently tested by third-party HPLC and mass spectrometry, with a batch-specific Certificate of Analysis published verifying ≥99% purity.

Is IGF-1 LR3 for human use?

No. IGF-1 LR3 sold by Woosh Labs is strictly for in-vitro laboratory research by qualified professionals. It is not for human or veterinary use of any kind.