Before buying IGF-1 LR3, check that the certificate names IGF-1 LR3 (Long R3 IGF-I) on its identity line, is for the 1 mg lot you receive, and reports both HPLC purity and measured content in mg. Clean Peptide sells IGF-1 LR3 as a 1 mg vial with an ILS Laboratories certificate. The current lot, ACE-1279625, measured 1.03 mg at 99.90% HPLC purity, with identity confirmed against an IGF-1 LR3 reference standard and fentanyl, heavy-metal, sterility and endotoxin results on the same certificate.
This page sets out what to check, using that certificate as the worked example. IGF-1 LR3 is not a short synthetic peptide like most of what we stock: it is an 83-residue recombinant protein, and that changes what a certificate can and cannot show.
First, be sure which molecule you are buying
“IGF-1” on a label can mean several different molecules. IGF-1 LR3 is one specific analogue of human insulin-like growth factor I:
| Names | IGF-1 LR3, Long R3 IGF-I, LR3IGF-I, Long [Arg3]-IGF-I |
|---|---|
| What “LR3” means | “Long”: a 13-residue N-terminal extension. “R3”: arginine in place of glutamate at position 3 of the IGF-I sequence. |
| Length | 83 residues (native mature human IGF-I has 70) |
| Disulfide bonds | Three: Cys19-Cys61, Cys31-Cys74, Cys60-Cys65 |
| Molecular weight | About 9.1 kDa. No authoritative source states a single molecular formula. |
| CAS number | 143045-27-6 |
| How it is made | Recombinantly, in E. coli |
Identity data as listed on our IGF-1 LR3 product page (sequence, disulfides and CAS from the GSRS substance registry, UNII M9L22Y19H9).
So a listing for “IGF-1”, “IGF-1 DES” (des(1-3) IGF-I, a different, shorter variant) or “Long IGF-1” without the R3 is not necessarily the same molecule. The name on the certificate’s identity line should be IGF-1 LR3 or Long R3 IGF-I.
What our IGF-1 LR3 certificate reports
| Lot and size | ACE-1279625, 1 mg |
|---|---|
| Laboratory and certificate | ILS Laboratories, COA-2026-IIZXM6 (Full QC Panel) |
| Received / analysed | 27 August 2026 / 9 September 2026 |
| Sample matrix and appearance | Lyophilised; good |
| Identity (HPLC-RTM) | IGF-1 LR3: confirmed |
| HPLC purity | 99.90% (spec 95.0% or higher) |
| Net peptide content | 1.03 mg (103.0% of label; “Report Only”) |
| Fentanyl screen | Immunoassay, 50 ng/mL cutoff: not detected |
| Heavy metals (ICP-MS) | As, Cd, Pb, Hg, Cr: not detected |
| Sterility (PCR) | No growth |
| Endotoxin (USP <85>) | 0.101 EU/mL (reported) |
| Overall | Pass |
Transcribed in October 2026 from the ILS certificate image on the lot page and checked against ILS’s portal record on 30 October 2026. The percentage of label is simple arithmetic on the certificate’s figure.
Six things to check before buying IGF-1 LR3
- The identity line names IGF-1 LR3. Ours reads “Identity (HPLC-RTM): IGF-1 LR3, Confirmed”. A certificate that says only “IGF-1” does not tell you which analogue was tested.
- It is for your lot and your size. The lot number on the certificate should match the vial. IGF-1 LR3 is sold here in one size, 1 mg, with one current lot.
- Measured content is in mg, not only purity. At 1 mg, a vial holds very little material, so the measured figure matters. Ours reads 1.03 mg. Purity says how clean the main peak is; it cannot say how much is in the vial.
- You know how to read 99.90%. ILS’s notes on this certificate say purity values are capped at 99.9% to reflect the instrument’s limit of detection. 99.90% means at or above the cap.
- The panel goes beyond purity. A fentanyl screen, heavy metals, sterility and endotoxin are all on this certificate. If a certificate has only purity, the rest was not tested.
- You can check it with the laboratory. The lot page links to ILS’s own record of this certificate. Our guide to verifying a peptide COA shows the lookup step by step.
What an IGF-1 LR3 certificate does not tell you
Most of the peptides we sell are short chains made by chemical synthesis. IGF-1 LR3 is an 83-residue recombinant protein with three disulfide bonds, and the certificate’s methods were not designed to describe that structure in full:
- Identity is by HPLC retention time. ILS compares the sample’s main peak with an IGF-1 LR3 reference standard run on the same method. The certificate does not report a measured mass, does not read the sequence, and does not test the three disulfide bonds.
- No chromatogram is printed. ILS’s certificates for Melanotan II, survodutide and thymosin alpha-1 each print the HPLC trace; the IGF-1 LR3 certificate, and its portal record, do not.
- There is no test specific to recombinant production. The panel is the same Full QC Panel ILS runs on synthetic peptides.
- Sample details come from the client. ILS states that product names, lot numbers and labelled content are supplied by the submitting party and that results describe only the sample tested. That is why the lot match and the laboratory lookup matter.
None of this is a failing of the result: it is the scope of the test. Our guides to peptide testing and the COA glossary explain each method and abbreviation.
The IGF-1 LR3 certificates on file today
This table is read from the same certificate records as the product page, so it changes when a new lot goes on sale. Every lot is also listed on the IGF-1 LR3 COA page.
| Size | Lot | Laboratory | Analysed | HPLC purity | Measured content | Identity |
|---|---|---|---|---|---|---|
| 1mg | ILS Laboratories | 9 Sep 2026 | 99.90% | 1.03 mg | Confirmed |
Transcribed from the certificate issued for each size on sale today. Open the IGF-1 LR3 certificates Every IGF-1 LR3 COA, lot by lot
Where to buy IGF-1 LR3 with a COA for each lot
Clean Peptide is a US store, cleanpeptide.com, operated by Helios LLC in Winston-Salem, North Carolina (about us). It sells IGF-1 LR3 as a 1 mg lyophilised vial for laboratory research only, and publishes each lot’s certificate on the product page and in the COA library. For the other compounds in the growth hormone axis we stock, see tesamorelin vs ipamorelin; for how our measured content compares with the label across every lot, see why a COA can show more than the label.
