Research use only. Not for use in humans or animals. All products and information on this site are provided strictly for in-vitro laboratory research purposes. They are not for use in humans or animals, and are not drugs, foods, cosmetics, or medical devices.
What Is Semax? A Research Peptide Overview
Semax is a synthetic peptide derived from a fragment of adrenocorticotropic hormone (ACTH) — specifically the ACTH(4–10) region — with a C-terminal modification. It is studied in neuroscience research and is one of the two most-discussed "research nootropic" peptides, alongside selank. This overview covers what Semax is, how it compares to selank, and how to source research-grade material.
Semax at a glance
| Property | Value |
|---|---|
| Name | Semax |
| Class | Synthetic ACTH(4–10) analog with a Pro-Gly-Pro C-terminal extension |
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro |
| Appearance | White lyophilized powder |
Research background
Native ACTH(4–10) is a short, rapidly degraded fragment. Semax adds a Pro-Gly-Pro tripeptide to the C-terminus, which resists enzymatic breakdown and extends its stability in laboratory systems. This modification is why Semax is studied where the unmodified ACTH fragment is not.
What Semax is studied for
In laboratory and preclinical research, Semax is studied for:
- Neurotrophic signaling — models involving BDNF (brain-derived neurotrophic factor) expression.
- Neuroprotection — cell and animal models of neural stress.
- Cognitive-model research — behavioral studies in animal models.
Semax offered here is a research chemical for laboratory use only. Not for use in humans or animals.
Semax vs selank
Both are Russian-developed research peptides studied in neuroscience, and researchers frequently compare them:
- Semax — ACTH(4–10)-derived; studied primarily around neurotrophic (BDNF) signaling.
- Selank — derived from the immunomodulatory peptide tuftsin; studied more around anxiolytic-model and immune-signaling research.
They are structurally unrelated despite being grouped together, and are sometimes studied side by side.
Forms of Semax
Semax is studied both as the base peptide and as N-acetyl Semax (and N-acetyl Semax amidate), acetylated forms studied for extended stability in solution. All are research materials.
How research-grade material is verified
Every batch from a credible US supplier should arrive with a third-party Certificate of Analysis (COA) for that exact lot. Peptide Technologies publishes a COA on every batch and ties it to a QR code on the vial. A complete COA reports:
- Identity — mass spectrometry (ESI-MS) confirming the observed mass matches the theoretical mass of the target sequence.
- Purity — reverse-phase HPLC, reported as percent peak area at a fixed wavelength (typically 220 nm). Research-grade material is ≥99% by area.
- Net content — gravimetric confirmation the vial holds the stated mass within tolerance.
- Endotoxin — LAL assay below research-grade thresholds.
If a vendor cannot show a lot-specific COA, you cannot verify what is in the vial. Browse the full COA library →
How to source research-grade material
For laboratory research, sourcing quality comes down to a few checks:
- Lot-specific COA from an accredited, independent laboratory — not a generic marketing PDF.
- HPLC purity ≥99% by peak area, with the chromatogram shown.
- US synthesis and finishing, so the chain of custody is documented end to end.
- Cold-chain shipping for lyophilized material, so the product arrives stable.
Peptide Technologies meets each of these and publishes a third-party COA for every lot. Browse the public COA library →
FAQ
What is Semax?
Semax is a synthetic peptide derived from the ACTH(4–10) fragment with a Pro-Gly-Pro C-terminal extension, studied in neuroscience research on neurotrophic signaling and neuroprotection.
What is the difference between Semax and selank?
Semax is ACTH-derived and studied around neurotrophic (BDNF) signaling; selank is tuftsin-derived and studied around anxiolytic-model and immune signaling. They are structurally unrelated.
What is N-acetyl Semax?
N-acetyl Semax is an acetylated form of Semax studied for extended stability in solution. An amidated variant (N-acetyl Semax amidate) is also studied.
How is Semax verified?
Research-grade Semax is verified by HPLC for purity, mass spectrometry for identity, and an LAL endotoxin assay, reported on a lot-specific third-party COA.
Is Semax a research chemical?
Yes. Semax supplied by Peptide Technologies is a research chemical for laboratory use only. Not for use in humans or animals.