Growth Hormone Secretagogues
IGF-1 LR3 (Long R3 IGF-1) is an 83-residue recombinant analog of insulin-like growth factor-1 carrying a 13-residue N-terminal extension and an arginine substitution at position 3. That substitution sharply reduces affinity for IGF binding proteins, leaving a much larger free fraction available to the IGF-1 receptor in serum-containing culture — the reason the analog, not native IGF-1, became the standard reference tool in cell-culture receptor work.
Reference data researchers look up before ordering igf-1 lr3. Every lot ships with documentation matching the batch number printed on the vial.
Each igf-1 lr3 lot is released only after an independent purity panel. HPLC quantifies purity, LC-MS confirms molecular identity, and the lot-matched certificate is published so the number on your vial matches the report you download.
IGF-1 LR3 ships lyophilized. Reconstitute with bacteriostatic water containing 0.9% benzyl alcohol. The ratios below assume a standard U-100 insulin syringe.
PX1 Research synthesizes and fills igf-1 lr3 in a US cGMP-compliant facility rather than reselling imported material, so purity documentation traces back to the production lot. Multi-vial pricing steps down at 3, 5 and 10 vials, and subscription intervals are available on the product page.
Convert vial strength and bacteriostatic water volume into exact insulin-syringe unit marks.
Peptide reconstitution calculator
Concentration
5 mg/mL
Draw volume
0.05 mL
Insulin syringe
5 units (IU)
U-100 insulin syringe (100 units = 1 mL)
10 mg + 2 mL = 5 mg/mL. A 250 mcg dose = 5 units on a U-100 syringe (40 doses per vial).
For laboratory and research use only. Not for human or veterinary use.
Need solvent? Buy bacteriostatic water (10mL / 30mL)
Long R3 — the 13-residue N-terminal extension (Long) plus the arginine substitution at position 3 (R3).
The folded 83-residue protein is far more soluble below its isoelectric point, so a dilute acetic acid vehicle gives a clear solution where neutral water can leave aggregated or undissolved material.
Native IGF-1 is largely sequestered by IGF binding proteins in serum. The R3 substitution reduces that binding, so a larger free fraction of the analog remains available to the receptor in the same medium.
Aggregation is the main failure mode of a folded, disulfide-bonded protein and is invisible on inspection, so the lot certificate reports more than reversed-phase purity.
Yes. Every igf-1 lr3 lot has a published, lot-matched COA showing HPLC purity and LC-MS identity confirmation.
Store the lyophilized vial at -20°C protected from light. Once reconstituted with bacteriostatic water, keep it refrigerated at 2–8°C.