Semax
A synthetic heptapeptide analogue of adrenocorticotropic hormone fragment 4-10, extended with a Pro-Gly-Pro tail.
- Purity
- 99.2%
- Lot
- PU-C88D
- CAS
- 80714-61-0
- MW
- 813.90 g/mol
- Format
- Lyophilized powder
- Third-party tested
- Discreet packaging
- Same-day shipping
- Encrypted checkout
For research use only. Not for human consumption.
Mechanism of Action
Semax is an analogue of ACTH(4-10) extended at the C-terminus with proline-glycine-proline. The parent fragment lacks the corticotropic activity of the full hormone; the added tripeptide tail was introduced to slow enzymatic degradation, and two studies from 1991 and 1993 characterised the degradation of the parent and the analogue by rat blood and serum enzymes directly.
Mechanistically, published work has reported regulation of brain-derived neurotrophic factor and its receptor TrkB in the hippocampus, effects on dopaminergic and serotonergic systems, and modulation of immune-response gene expression in ischaemia models. A 2025 British Journal of Pharmacology paper reported an interaction with the mu-opioid receptor gene Oprm1.
Research Findings
Primary studies published in Brain Research, the Journal of Neurochemistry and Neurochemical Research examined BDNF and TrkB expression, receptor binding and monoaminergic activation in rodent brain. Transcriptomic work examined gene-expression profiles after experimental ischaemia.
A 2020 connectomic study examined Semax and Selank effects together. Much of this literature originates from Russian research groups, and independent replication elsewhere is limited - a point reviewers have consistently raised.
Storage & Reconstitution
Sealed lyophilized vials are stored in the dark. The peptide-formulation literature regards the dry solid as the stable state and the solution as the fragile one: refrigeration at 2-8 degrees C is standard for short holding periods, and minus 20 degrees C or colder for long-term storage. Vials are brought to room temperature before opening so that atmospheric moisture does not condense onto the cold solid.
For reconstitution, the diluent is added slowly down the inner wall of the vial rather than directly onto the cake, and the vial is swirled rather than shaken - agitation at an air-liquid interface is a well-documented driver of peptide aggregation. The solid should dissolve to a clear, particle-free solution; persistent cloudiness or visible particulate indicates the material should not be used.
Reconstituted solution is held at 2-8 degrees C and protected from light. Freeze-thaw cycling is the single most avoidable cause of loss, so where a solution must be frozen it is aliquoted first into single-use volumes. Working aliquots are labelled with the lot number so that any result can be traced back to the certificate of analysis for that lot.
- Physical form
- Lyophilized powder, sealed vial
- Sealed storage
- 2-8 C short term / -20 C long term
- Reconstituted
- 2-8 C, protected from light
- Diluent
- Bacteriostatic water, added down the vial wall
- Avoid
- Shaking, freeze-thaw cycling, direct light
Handling summary
References
Every entry below links to its PubMed record. Publication is not endorsement: several of these papers report limitations, negative findings or adverse events, and they are listed for that reason.
- [1]Functional Connectomic Approach to Studying Selank and Semax Effects(opens PubMed in a new tab)
Dokl Biol Sci · 2020 · PMID 32342318
- [2]
- [3]
- [4]
- [5]
- [6]