Fragment 176-191 10mg

Fragment 176-191 is a synthetic 16-residue peptide matching the C-terminal sequence (residues 176–191) of human growth hormone, with one intramolecular disulfide bond. Contexx Research supplies Fragment 176-191 in Canada as a 10 mg lyophilized reference peptide for structure–function and analytical research.

Fragment 176-191 specifications

Research overview

Researchers have studied synthetic C-terminal fragments of growth hormone since the 1970s to find out which regions of the 191-residue hormone account for its different biological activities. Early experiments by Ng and colleagues tested synthetic C-terminal fragments in rodent models of carbohydrate metabolism [1].

In the 1990s, studies on the 177–191 sequence characterised its effects on lipogenesis in isolated rodent adipose tissue, an early example of separating domain-specific activities from the intact hormone [2]. That line of work later produced related analogues such as AOD-9604.

More recent in-vitro research has used the 176–191 peptide in other ways. A 2022 study, for example, combined it with doxorubicin-loaded chitosan nanoparticles and examined cytotoxicity in MCF-7 breast-cancer cells [3]. The fragment is also a reference analyte for LC-MS identification methods.

Selected references

1. Ng FM et al. Am J Physiol. 1978. PubMed 645904
2. Wu Z et al. Biochem Mol Biol Int. 1993. PubMed 8358331
3. Habibullah MM et al. Drug Des Devel Ther. 2022. PubMed 35783198

Storage and handling

Fragment 176-191 ships as a lyophilized (freeze-dried) powder. Dry material is far more stable than material in solution, so keep it in its dry, sealed state until you need it.

• Store unopened vials of Fragment 176-191 at −20 °C, dry and protected from light. Let the vial reach room temperature before opening to limit condensation.
• Prepare stock solutions in a solvent suited to your assay, label them with concentration and date, and keep them at 2–8 °C for short-term use.
• For longer storage of solutions, divide them into single-use aliquots and freeze them; avoid repeated freeze–thaw cycles.
• Handle with gloves and eye protection, following your laboratory’s standard chemical-hygiene practice.

See our guide to storing lyophilized peptides in the lab for more detail.

Quality and testing

Contexx Research independently tests every batch it releases. A lot-specific COA for Fragment 176-191 isn’t linked on this page yet. For questions about testing, contact info@contexxresearch.ca.

We don’t list purity figures in this description; the lot COA is the reference for identity and purity. Researchers should confirm identity and concentration with their own analytical methods where their protocol requires it.

Frequently asked questions

What’s included when I order Fragment 176-191 10 mg?

One sealed vial containing 10 mg of Fragment 176-191 as a lyophilized powder. Reconstitution solution is sold separately.

Does Fragment 176-191 come with a Certificate of Analysis (COA)?

Every batch Contexx Research releases is independently tested. A lot-specific COA isn’t linked on this page yet; for testing questions, contact info@contexxresearch.ca.

How fast is shipping in Canada?

Orders are processed Monday to Friday, and most orders ship within 24 hours from Mississauga, Ontario, in secure, tamper-evident packaging. Orders placed on Friday afternoon (after the 12:00 PM ET cut-off) ship on Monday, when Canada Post resumes pickup, or on the next business day if Monday is a statutory holiday. Once your order ships, delivery typically takes 1–3 business days in Ontario and Quebec and 2–6 business days in the rest of Canada, and a tracking number is emailed to you. Orders over $250 CAD shipped within Canada qualify for free standard shipping. See our Shipping Policy for details.

How should Fragment 176-191 be stored?

Store unopened vials at −20 °C, dry and protected from light. After reconstitution, keep solutions at 2–8 °C for short-term use, or freeze single-use aliquots and avoid repeated freeze–thaw cycles.

What does “research use only” mean?

“Research use only” means Fragment 176-191 is sold only as a reference material for in-vitro laboratory and analytical research by qualified professionals. It is not for use in humans or animals, not for diagnostic use, and not a drug, natural health product, food, supplement or cosmetic.

Research use only

Fragment 176-191 is sold by Contexx Research Inc. strictly as a reference material for in-vitro laboratory research and analytical use by qualified professionals. It is not a drug, natural health product, food, dietary supplement or cosmetic. It is not intended for use in humans or animals, for diagnostic purposes, or for ingestion or any other form of administration to a living organism. Nothing on this page describes or implies any effect in humans or animals. Purchasers are responsible for handling, storage and disposal in line with applicable laws and their institution’s policies. By ordering, you confirm that you are purchasing for legitimate laboratory research and agree to our Terms and Conditions.