Description
PrymaLab · Research use only
Preloaded Autoinjector | IGF1 LR3 | 3ml Pen | 1mg/ml
Long R3 IGF-1 in bacteriostatic water at 1 mg/mL, 3 mg in a preloaded 3 mL pen
IGF-1 LR3 is Long R3 IGF-1, an 83-residue analogue of human insulin-like growth factor 1 built with a 13-residue N-terminal extension and arginine at position 3 so that it binds IGF-binding proteins weakly. This listing is a preloaded autoinjector pen: 3 mg of the protein dissolved in 3 mL of bacteriostatic water. Research on it comes from cell culture and rat studies of IGF-I potency and binding-protein interactions.
Specifications
| Property | Value |
|---|---|
| Compound | IGF-1 LR3 Long R3 IGF-1; recombinant human IGF-1 analogue with a 13-residue N-terminal extension and Glu3→Arg |
| CAS number | 143045-27-6 |
| Molecular formula | C 400 H 625 N 111 O 115 S 9 (reduced-chain calculation) |
| Theoretical mass | 9117.6 Da (reduced-chain calculation; 9111.6 Da with the three disulfides formed) |
| Sequence / structure | H-MFPAMPLSSLFVNGPRTLCGAELVDALQFVCGDRGFYFNKPTGYGSSSRRAPQTGIVDECCFRSCDLRRLEMYCAPLKPAKSA-OH (83 residues; three intrachain disulfides; free N- and C-termini) |
| Contents | IGF-1 LR3: 3 mg per 3 mL pen (0.1% w/v) |
| Form | Sterile aqueous solution in bacteriostatic water (0.9% benzyl alcohol), supplied in a 3 mL glass cartridge inside a preloaded autoinjector pen fitted with a needle |
| Storage, sealed | Store at 2–8 °C in the original carton, protected from light |
| Safety data sheet | PL-SDS-088 |
What is in the pen
Each pen carries a 3 mL glass cartridge of sterile solution with IGF-1 LR3 at 0.1% w/v, which is 1 mg/mL and 3 mg per pen. At the certificate’s folded mass of 9111.6 Da, 1 mg/mL is about 0.11 mM. The diluent is bacteriostatic water with 0.9% benzyl alcohol. The safety data sheet does not classify the protein as hazardous; benzyl alcohol is listed as harmful if swallowed or inhaled, an eye irritant and a possible skin sensitiser. Storage follows the safety data sheet: keep the pen at 2 to 8 °C in its carton, away from light, capped once in use, and never frozen. Discard a pen whose solution has frozen, discoloured or become cloudy. The IGF-1 LR3 1 mg vial holds the same protein freeze-dried, and peptide pen vs vial compares the two formats.
What the research covers
Long R3 IGF-I was first made in Escherichia coli as a fusion protein, with a 13-residue lead made of methionyl porcine growth hormone’s first 11 amino acids plus Val-Asn, and arginine replacing glutamate 31. The extension seemed to help the chain fold correctly during production, and in L6 myoblasts the long analogues outperformed authentic IGF-I1. The design is aimed at the IGF-binding proteins, a family of six related proteins that bind IGF-I and IGF-II tightly and can block IGF action2.
In a 14-day rat study, LR3IGF-I, which the authors described as binding those proteins very weakly, was substantially more potent than IGF-I on body weight gain, nitrogen retention and food conversion, while body proportions stayed broadly as they were3. Growth hormone tested alongside did not stimulate growth3.
These are cell and rodent results, and none of them involved a protein held in bacteriostatic water. Whether IGF-1 LR3 stays folded and active over weeks in a preserved solution is not addressed by any of these papers. The IGF-1 LR3 guide covers the wider literature and sets LR3 beside IGF-1 DES.
How each lot is tested
Every lot is tested in PrymaLab’s own laboratory in Ashland, Kentucky before release: RP-HPLC for purity, LC-MS for identity, Karl Fischer titration for water, LAL for endotoxin and USP <71> for sterility. Published certificates are listed on the results page and can be checked by number and key on the verify page. The certificate covers the peptide lot used to fill the pen, not the finished solution. These are in-house results from PrymaLab Analytical, not an independent test, and the lab is not accredited to ISO 17025. The third-party testing guarantee on this page still applies: if any independent laboratory finds the wrong compound, or less than the stated purity or amount, the order is refunded and the cost of the test is reimbursed.
Frequently asked questions
How does the pen differ from the 1 mg vial?
The vial is 1 mg of freeze-dried protein stored at −20 °C until a laboratory dissolves it. The pen holds 3 mg already in bacteriostatic water at 1 mg/mL and is stored at 2 to 8 °C. The protein, Long R3 IGF-1, is the same in both.
Why must the pen never be frozen?
The safety data sheet says not to freeze it and to discard a pen whose solution has frozen. IGF-1 LR3 is a folded protein held together by three disulfides, and even the dry protein's certificate warns against repeated freeze-thaw cycles.
What does the certificate cover?
The protein lot used to fill the pen. It reports that lot's RP-HPLC purity, LC-MS identity, water, endotoxin and sterility; the finished cartridge solution is not separately certified.
Is the pen for use in people?
No. It is a research reagent sold only for laboratory work, not approved for human or veterinary use, and it must not be given to people or animals.
References
- Francis GL, Ross M, Ballard FJ, et al. Novel recombinant fusion protein analogues of insulin-like growth factor (IGF)-I indicate the relative importance of IGF-binding protein and receptor binding for enhanced biological potency. J Mol Endocrinol. 1992;8(3):213-23. DOI · PubMed
- Baxter RC. Insulin-like growth factor (IGF)-binding proteins: interactions with IGFs and intrinsic bioactivities. Am J Physiol Endocrinol Metab. 2000;278(6):E967-76. DOI · PubMed
- Tomas FM, Knowles SE, Chandler CS, et al. Anabolic effects of insulin-like growth factor-I (IGF-I) and an IGF-I variant in normal female rats. J Endocrinol. 1993;137(3):413-21. DOI · PubMed
Research use only
For laboratory research use only. This product is not a drug, food, cosmetic or dietary supplement, is not approved by the FDA or any comparable authority for human or veterinary use, and must not be given to people or animals. It is sold to qualified researchers and institutions, and the buyer is responsible for lawful handling and disposal.
Other formats of IGF1 LR3
IGF1 LR3 is also stocked as IGF-1 LR3 Nasal Spray, IGF-1 DES Nasal Spray, IGF-DES 2mg and IGF-DES 1mg/ml preloaded 3ml pen. Each listing states its own quantity and concentration, and the pen and vial comparison explains what changes between formats.
10 reviews for Preloaded Autoinjector | IGF1 LR3 | 3ml Pen | 1mg/ml