IGF-1 LR3 Testing
Modified IGF-1 with Arg3 substitution and 13-aa N-terminal extension; ~3x potency, longer half-life.
Mechanism of action
Modified IGF-1 with Arg3 substitution (prevents IGF binding protein interaction) and a 13-residue N-terminal extension (improves stability). The combination yields ~3× potency over native IGF-1 with substantially longer half-life. Produced recombinantly in E. coli.
Research areas
- ●Anabolic / muscle research
- ●Wound healing
- ●Cell culture (the primary legitimate use)
Dosing in the literature
No human FDA approval. Veterinary and bodybuilding research uses 20–80 μg/day SC.
For research/informational purposes only — not medical advice.
What we test on IGF-1 LR3
SEC-HPLC for aggregation, RP-HPLC for purity, intact-mass LC-MS, non-reducing tryptic mapping for disulfide verification, HCP ELISA, mandatory LAL endotoxin.
- ✓SEC-HPLC (aggregation)
- ✓RP-HPLC purity
- ✓Intact-mass LC-MS
- ✓Endotoxin (LAL)
Common impurities & failure modes
- Misfolded protein
Incorrect disulfide pairings produce inactive variants with identical mass. Non-reducing tryptic mapping detects.
- Aggregates
Dimers and higher-order aggregates are common; SEC quantifies.
- Host-cell protein (HCP)
E. coli proteins co-purifying with the product; ELISA quantifies.
- Endotoxin
E. coli-derived material; LAL mandatory.
- Truncated forms
Proteolysis during expression or purification.