Semax reconstitution protocol

This protocol describes the reconstitution and storage of lyophilized Semax in standard research workflows. Semax is a synthetic 7-amino-acid compound derived from ACTH (4–7) extended with a Pro-Gly-Pro tail. It's studied predominantly for nootropic and neuroprotective effects in Russian neuroscience literature. Values below reflect published handling literature; study design is the responsibility of the qualified investigator.

At a glance

Parameter	Value
Recommended diluent	Bacteriostatic Water (USP, 0.9% benzyl alcohol)
Recommended volume (10 mg vial)	2.0 mL
Final concentration	5 mg/mL
Stability — lyophilized	≥24 months at -20 °C, sealed, light-protected
Stability — reconstituted	30 days at 2–8 °C in original vial
Routes studied	Intranasal (most common in Russian literature), subcutaneous, intraperitoneal

Procedure

1. Equilibrate the vial to room temperature.
2. Sterile prep: wipe stopper with isopropyl. Use sterile syringe and needle.
3. Inject diluent slowly along the inner wall.
4. Swirl gently. Dissolution completes within 30 seconds.
5. Verify: solution should be clear and colorless.

Compound notes

Semax (Met-Glu-His-Phe-Pro-Gly-Pro) is the 4–7 fragment of adrenocorticotropic hormone (ACTH) with a Pro-Gly-Pro C-terminal extension. The ACTH fragment is responsible for the cognitive effects observed in older literature; the Pro-Gly-Pro extension increases enzymatic stability so the compound survives administration long enough to act centrally.

Most published research focuses on:

• Neuroprotection in stroke models (the original Russian clinical indication)
• Cognitive enhancement in rodent learning and memory tasks
• BDNF and NGF upregulation in CNS tissue
• Attention and stress-response modulation

The intranasal route is unusually well-characterized for Semax — it bypasses first-pass metabolism and allows direct nose-to-brain transfer through the cribriform plate. For research models studying central effects, intranasal administration produces measurable CSF concentrations within minutes; subcutaneous administration produces lower CSF exposure due to limited blood-brain barrier penetration.

The compound is well-behaved in standard buffers and tolerant of typical ionic strength variation. Plasma half-life is short (~15–30 minutes); CNS effects persist longer due to the receptor-binding kinetics rather than the pharmacokinetic profile.

Storage

Reconstituted Semax is stable for approximately 30 days at 2–8 °C. For longer storage, aliquot into sterile single-use tubes and freeze at -20 °C or colder. Lyophilized stability is ≥24 months at -20 °C light-protected.

Notes

This protocol describes reconstitution parameters from published handling literature. It is not a recommendation for any specific research protocol or design. For research use only. Not for human or veterinary use.

References

1. Asmarin IP, Nezavibatko VN, Levitskaya NG, et al. Nootropic and analgesic activity of semax: the heptapeptide [Met-Glu-His-Phe-Pro-Gly-Pro]. Patol Fiziol Eksp Ter 1997;1:11–17. PMID: 9221920
2. Dolotov OV, Karpenko EA, Inozemtseva LS, et al. Semax, an analogue of adrenocorticotropin (4-10), binds specifically and increases levels of brain-derived neurotrophic factor protein in rat basal forebrain. J Neurochem 2006;97 Suppl 1:82–86. PMID: 16635253