Key highlights
Product specifications
| Compound Class | Growth Hormone Secretagogue · Ghrelin Receptor (GHSR-1a) Agonist |
|---|---|
| Concentration | 25mg/mL |
| Composition | USP-grade PEG-400 base, MK-677 (≥98% purity) |
| CAS Number | 159752-10-0 |
| Chemical Formula | C27H36N4O5S |
| Molar Mass | 528.66 g/mol |
| Half-Life | ~24 hours |
| Synonyms | Ibutamoren, Nutrobal, MK-0677, L-163,191 |
| Volume | 30 mL per bottle |
| Verified Purity | Batch-tested to 99.87% (HPLC) |
| Terms | For laboratory research use only. Not for human or animal consumption. |
Independently verified99.87% pure
Every batch is analyzed by an accredited US third-party laboratory before it ships.
Purity and identity confirmed by MZ Biolabs (Tucson, AZ), a US DEA-licensed analytical facility, via HPLC purity analysis and mass-spectrometry identity confirmation under GLP standards.
Every COA is published openly, batch-dated, and matched to the product you receive — no login required.
Each bottle is formulated and verified for consistent label-to-bottle accuracy across studies.
Storage & handling
Built to preserve compound integrity throughout your research timeline.
- Storage: Keep in a cool, dry place away from direct sunlight to maximize shelf life.
- UV-resistant glass bottle with fixed glass dropper to minimize degradation and avoid plasticizer (BPA) leaching.
- Tamper-proof seal to ensure integrity in transit.
- Graduated 1 mL glass pipette included for precise measurement.
- Evaporation-resistant formulation and packaging for stable storage.
Why source MK-677 from Sports Technology Labs
Quality control across the research-compound industry is inconsistent, which makes third-party verification essential. A 2017 analysis published in JAMA examined 44 products marketed online as SARMs and reported wide gaps between labels and contents.
Source: Van Wagoner et al., JAMA, 2017 (ref. 2).
Minimum 98% purity, verified by MZ Biolabs (Tucson, AZ), an accredited US laboratory.
Suspended in the highest grade carrier and bottled in America.
Prevents BPA leaching and avoids contamination from external tools.
Transparent business, standard payment methods, no misrepresentation.
What is MK-677?
MK-677 (Ibutamoren) is a non-peptide ghrelin receptor (GHSR-1a) agonist and growth hormone secretagogue. Mechanistically, it binds and activates the GHSR-1a receptor — the same receptor targeted by the endogenous peptide ghrelin — at sites in the hypothalamus and anterior pituitary. In the research literature this receptor activity is characterized as stimulating signaling along the growth hormone–IGF-1 axis (ref. 1). Unlike peptide-based secretagogues, MK-677 is orally bioavailable in study models.
Although MK-677 is frequently catalogued alongside selective androgen receptor modulators (SARMs), this is a cataloguing convention rather than a pharmacological classification: it is structurally and mechanistically distinct and does not bind the androgen receptor (ref. 1). It has been an investigational compound since the 1990s and remains experimental, supplied strictly for laboratory research. Sports Technology Labs makes no claims regarding its effects, and nothing in this listing should be interpreted as describing outcomes in humans.
Important regulatory information
MK-677 is an investigational compound. It is not approved by the FDA and is not a dietary supplement, drug, or food. Marketing it for human ingestion is unlawful.
Listed by the World Anti-Doping Agency under S2 (Peptide Hormones, Growth Factors, Related Substances and Mimetics), banned both in- and out-of-competition (ref. 3).
In the United States, MK-677 is not a controlled substance and may be legally purchased and possessed for laboratory research use.
Sports Technology Labs are chemical suppliers, not medical providers. We do not condone or encourage consumer use of research compounds.
Scientific references
- Patchett AA, et al. Design and biological activities of L-163,191 (MK-0677): a potent, orally active growth hormone secretagogue. Proc Natl Acad Sci USA. 1995;92(15):7001–7005.
- Van Wagoner RM, et al. Chemical composition and labeling of substances marketed as SARMs and sold via the internet. JAMA. 2017;318(20):2004–2010.
- WADA Prohibited List (2025), Section S2: Peptide Hormones, Growth Factors, Related Substances and Mimetics. WADA.org.
Research use only. All products on this website are intended exclusively for laboratory research and development. They are not for human or animal consumption. These statements have not been evaluated by the U.S. Food and Drug Administration, and these products are not intended to diagnose, treat, cure, or prevent any disease.
