IGF-1 LR3 is a recombinant Long R3 IGF-1 analog (CAS 946870-92-4). Formula/mass anchors and lot COA purity panels. Research use only.
IGF-1 LR3 is a recombinant / modified Long R3 analog of human Insulin-like Growth Factor-1. It is a discrete research material with its own CAS, formula, molar mass, and lot documentation — not a catalogue nickname for every “IGF” listing, and not a synonym for native IGF-1 or unrelated GH-axis research SKUs.
If you found “igf-1 lr3,” “igf-1 lr3 coa,” “recombinant igf-1 long r3,” “long r3 igf-1,” or “igf-1 lr3 third party tested” in a listing, the useful questions are which registry fields the seller claims, what “Long R3” means as naming literacy, whether the certificate matches those anchors, and how the vial lot is documented. Aliases vary; registry fields and certificates do not.
This page covers Peptide Foundry’s published identity anchors, Long R3 structural naming, the purity panels a research buyer should demand, and a worked Freedom Diagnostics lot for the live 1 mg option — then soft-handoffs to the IGF-1 LR3 research product page. Research use only.
Key points
- IGF-1 LR3 = recombinant / modified analog of human IGF-1 with a 13-amino-acid N-terminal extension (“Long”) and arginine substitution at position 3 (“R3”); supplied as lyophilized research material.
- Peptide Foundry catalog anchors (live PDP): CAS 946870-92-4, formula C400H625N111O115S9, molar mass 9117.6 g/mol — match certificate fields to these claims. A letter sequence is not listed on the live PDP and is not invented here.
- SKU
PF-IGF-1-LR3; live size option 1 mg lyophilized — match each vial to its own lot certificate (current worked example = IG312 / Freedom Diagnostics).- Demand a lot-matched COA: HPLC purity with method when stated, identity method (MS and/or HPLC), named laboratory, and downloadable lot PDF; “third-party tested” or “high purity” without lot + named lab is unfinished.
- Research use only — not for human or veterinary use; not an anabolic, muscle-growth, recovery, anti-aging, bodybuilding, or IGF-therapy consumer product.
What is IGF-1 LR3?
IGF-1 LR3 is a recombinant analog of human Insulin-like Growth Factor-1 (IGF-1). The research material on this page is that defined modified analog with the published registry anchors below — not a crude tissue extract and not a brand stack.
Naming literacy only: “Long” refers to a 13-amino-acid extension at the N-terminus; “R3” refers to an arginine substituted for glutamic acid at position 3. Those modifications are characterized in published work for altered IGF-binding-protein (IGFBP) affinity in preclinical assays. That is structural / naming literacy — not a therapy claim and not a product-benefit story.
A short historical note anchors naming only. Late 1980s / early 1990s modified IGF-1 analog work associated with GroPep (Adelaide) and related literature characterized binding-profile changes versus native IGF-1. That is origin and naming history — not registry proof and not a reason to treat every “IGF” nickname as interchangeable.
Physical form on research listings is lyophilized solid (white powder on the current certificate). Peptide Foundry’s current catalog documents describe lyophilized material under SKU PF-IGF-1-LR3 at a 1 mg size option. Appearance is a handling observation — not a purity proof and not a substitute for HPLC or identity data on a certificate.
Market aliases include IGF-1 LR3, IGF1 LR3, IGF-1-LR3, Long R3 IGF-1, LR3 IGF-1, and IGF-1 Long Arg3. Aliases help search and inventory. They are not identity proof until you have CAS, formula, molar mass, Long R3 framing, and a lot-matched certificate. The live Peptide Foundry PDP does not publish a one-letter sequence; this page follows that publication set and does not invent one.
Chemical identity anchors
Peptide Foundry publishes a fixed identity set for single-vial IGF-1 LR3. The values below match the live catalog chemistry table at the time of writing. Confirm against the current product page if a lot or chemistry block rotates after publish.
Naming and structural class
Class: recombinant / modified Long R3 IGF-1 analog (13-aa N-terminal extension; Arg-3 substitution). SKU PF-IGF-1-LR3; size option on the live listing at publish time: 1 mg lyophilized.
CAS, formula, and molar mass
| Field | Peptide Foundry catalog (live /product/igf-1-lr3/) |
|---|---|
| CAS | 946870-92-4 |
| Formula | C400H625N111O115S9 |
| Molar mass | 9117.6 g/mol |
| Class / naming | Recombinant / modified Long R3 IGF-1 analog (13-aa N-terminal extension; Arg-3) |
| SKU | PF-IGF-1-LR3 |
| Form | Lyophilized |
| Size (live option) | 1 mg |
Market pages sometimes round mass differently or recycle CAS strings across unrelated IGF nicknames. The practical rule is: match the vendor’s stated CAS + formula + molar mass + Long R3 framing to the lot COA, then prefer orthogonal identity (MS / HPLC) over the nickname alone.
What an IGF-1 LR3 COA should show
A certificate of analysis is stronger when it is lot-specific, names the laboratory, states methods, and can be checked via downloadable lot documentation or the issuing laboratory’s verification workflow. For the full verification workflow — batch match, named lab, HPLC versus identity, biosafety panels — see How to read a research-peptide COA.
Minimum research COA fields
- A lot / batch ID that matches the vial character for character
- Test or report date(s) and a named laboratory
- HPLC purity with method (and wavelength when stated)
- An identity method (MS and/or HPLC-RTM)
- Product name / composition consistent with the label and the vendor’s published anchors
“Third-party tested,” “high purity IGF-1 LR3,” or “99% pure” without a named lab and a lot number is an unfinished claim. Do not round a reported HPLC figure such as 98.509% up to “99%” when citing a certificate.
Stronger panels (when claimed)
- Mass-spectrometry or HPLC identity confirmation
- Net peptide content versus labeled mass when reported
- Endotoxin (for example LAL)
- Sterility / no growth, heavy metals, and illicit screens when claimed
These describe composition and contamination panels for research documentation. They are not a safety-for-human-use claim.
Worked example — lot IG312 (1 mg)
As published on the current Peptide Foundry IGF-1 LR3 listing at the time of writing for the 1 mg option:
| Field | Value |
|---|---|
| Lot | IG312 |
| Size | 1 mg |
| Laboratory | Freedom Diagnostics |
| Report date | 03/15/2026 |
| Purity | 98.509% (HPLC) |
| Net peptide content | 1.32 mg |
| Identity | Mass Spectrometry — confirmed |
| Test method | HPLC-UV / Mass Spectrometry |
| LAL endotoxin | Verified |
| Appearance | White Lyophilized Powder |
| COA number | 2603130190 |
Cite those figures as Peptide Foundry–published transparency for this lot — not a universal industry floor. Re-verify against the live product panel if the lot rotates after publish. The live PDP publishes downloadable Full COA and Endotoxin Test PDFs for this batch.
Three steps that travel with any lot, not just IG312:
- Match the lot number on the vial to the lot on the certificate.
- Confirm CAS, formula, and labeled mass against the certificate and the product label.
- Open the downloadable lot PDF and confirm the named-lab fields. The live Peptide Foundry IGF-1 LR3 listing links “Verify on Freedom Diagnostics” to the Freedom Diagnostics homepage (
https://freedomdiagnosticstesting.com). No lot-specific portal access code is published on the live PDP — do not invent one; teach lot → PDF → named lab matching.
Portable vendor criteria beyond a single SKU: USA research-peptide vendor criteria.
Related research peers (soft handoffs)
Research catalogues sometimes co-browse GH-axis materials beside IGF listings. Co-browsing is inventory adjacency — not a synonym set and not a protocol for combining materials.
- How to read a research-peptide COA and USA research-peptide vendor criteria — same trust workflow.
- Lyophilized peptide reconstitution — general lab diluent literacy without IGF-1 LR3 schedules.
- Optional soft GH-axis identity peers already live: TH9507 research identity, CJC-1295 + Ipamorelin research identity — identity peers only, never equal dual-CTA.
Match each vial to its own registry fields and lot certificate. Shared catalogue adjacency is literacy — not a stack recommendation.
Structural / naming literacy only
Keep Long R3 language at structural / naming literacy. It does not establish catalogue-product outcomes in people, and it does not convert a citation into a certificate.
| Naming / literature class | Acceptable framing on this page | Not used as product framing |
|---|---|---|
| Long = 13-aa N-terminal extension; R3 = Arg-3 substitution | Listing name Long R3 refers to published structural modifications versus native IGF-1 | “More potent for muscle,” super-IGF for people |
| Altered IGFBP affinity in preclinical assays | Characterized in preclinical assays for altered IGF-binding-protein affinity | Anabolic, recovery, or muscle-growth product claims |
Identity remains an analytical question answered by CAS, formula, Long R3 framing, and the lot COA. Pathway-as-benefit language is out of scope for this RUO identity page.
Storage and lab handling (lyophilized)
Standard laboratory practice for lyophilized synthetic peptides applies:
- Storage. Sealed vials at −20°C, protected from light and moisture. Lyophilized material is substantially more stable than solution.
- Temperature excursions. Brief ambient exposure in transit is normal for lyophilized material. Return vials to −20°C on arrival.
- Freeze–thaw. Minimize repeated freeze–thaw.
- Traceability. Keep the lot number with the material — lot number ties a vial back to its certificate.
Assay-specific handling follows your institution’s SOPs. This page does not publish personal reconstitution schedules or solution-use protocols for IGF-1 LR3. General lyophilized-material diluent literacy (without compound-specific schedules) lives at Lyophilized peptide reconstitution.
Common questions
What is IGF-1 LR3’s CAS, formula, and mass?
CAS 946870-92-4; formula C400H625N111O115S9; molar mass 9117.6 g/mol; recombinant / modified Long R3 IGF-1 analog. Peptide Foundry catalogs the material as SKU PF-IGF-1-LR3 (1 mg lyophilized option at publish time). The live PDP does not publish a letter amino-acid sequence; prefer registry fields over listing nicknames.
What does Long R3 mean?
“Long” names a 13-amino-acid N-terminal extension; “R3” names an arginine substitution at position 3. That is structural / naming literacy versus native IGF-1 — not a therapy claim. Match registry fields and the lot COA.
What makes an IGF-1 LR3 COA usable — and what does “third-party tested” require?
Lot match to the vial, a named laboratory, HPLC purity with method when stated, an identity method (MS and/or HPLC), and downloadable lot documentation (or another confirmable verify path). Stronger documentation adds net peptide content and endotoxin when claimed. Worked IG312 figures above — Freedom Diagnostics, HPLC 98.509%, MS identity confirmed, net 1.32 mg, COA number 2603130190 — are an example of that pattern on Peptide Foundry’s live listing. The live PDP does not publish a lot-specific portal access code; use the downloadable PDFs and the named-lab verify link as presented. Workflow detail: How to read a research-peptide COA.
Is this for anabolic use, muscle growth, recovery, anti-aging, IGF therapy, or human use?
No. Peptide Foundry supplies IGF-1 LR3 strictly for laboratory and research use by qualified researchers. Mentions of IGF-binding-protein affinity or structural Long R3 modifications in published preclinical literature are structural / literature-class context only — not product benefits and not human therapy. This page does not describe consumer finished goods, personal-use schedules, administration protocols, or stack recommendations. IGF-1 LR3 here is not a drug, supplement, consumer finished good, or veterinary product, and not for use in people or animals.
For the current lot certificate and product specifications, see the IGF-1 LR3 research product page. Related library reading: How to read a research-peptide COA, USA research-peptide vendor criteria, and Lyophilized peptide reconstitution.
Research use only. Nothing on this page describes or implies use in humans or animals. Structural / naming mentions of Long R3 modifications or IGF-binding-protein affinity refer only to preclinical literature contexts and are not product outcomes.