Molecular Characteristics
Complete Specifications
Structural Composition
Semax (7-amino-acid ACTH(4-7) analog peptide) + Selank (7-amino-acid tuftsin analog peptide)
Physical Properties
This blend combines Semax, a synthetic heptapeptide derived from the ACTH(4-10) fragment and extended with a Pro-Gly-Pro tail, with Selank, a synthetic heptapeptide analog of the tetrapeptide tuftsin carrying the same stabilising Pro-Gly-Pro motif. Because the formulation contains two structurally distinct peptides, overall molecular formula and molecular weight are inherently variable and depend on blend ratios and hydration state. Lyophilized presentation supports storage stability, while protection from moisture, light, and repeated freeze–thaw cycles helps maintain structural integrity and analytical consistency for laboratory and research applications.
Analysis & Documentation
Identity
Each production lot is checked against the reference structure recorded for this compound:
- Classification — Dual-peptide blend (Semax + Selank)
- Molecular formula — Variable (multi-component peptide blend)
- Expected mass — Variable (multi-component peptide blend)
- CAS registry — Not assigned (dual-peptide blend)
- Chain length — Variable (7 aa peptide + 7 aa peptide)
- PubChem CID — Not available
Analytical Methods
Testing is carried out per lot by an independent laboratory. The methods measure what the material is and how much of it is the target compound:
- RP-HPLC — reverse-phase separation of the target from process-related impurities; purity is reported as area percent of the main peak
- Mass spectrometry — observed mass compared against the expected molecular mass above
- Retention time — compared against a reference standard run under the same conditions
- Chromatogram — reproduced on the certificate so the peak and any shoulders can be inspected directly
Material & Documentation
What arrives, and how to tie it back to its paperwork:
- Appearance as supplied — White to off-white lyophilized powder (blend-dependent)
- Solubility — Water, phosphate-buffered saline (PBS)
- Lot number — printed on the container label and used to look up the certificate
- Certificate — indexed by lot at Certificates of Analysis
Laboratory Handling and Storage Protocols
Lyophilized Powder Storage
- Store at –20°C to –80°C in the original, sealed vial
- Protect from light exposure and moisture
- A desiccated storage environment is recommended
- Stability data suggests extended stability when stored at −20 °C or below.
Reconstituted Solution Storage
- Short-term storage: Up to 7 days at 4°C
- Long-term storage: Store at –20°C in aliquots
- Use single-use aliquots to preserve peptide integrity
- Minimize freeze–thaw cycles; single-use aliquots are strongly recommended
Stability Characteristics
Semax + Selank Blend is a synthetic multi-component peptide research formulation. Both components share a C-terminal Pro-Gly-Pro motif that confers relatively good resistance to enzymatic degradation compared with their parent fragments, but as a composite preparation stability still depends on proper cold storage of the lyophilized material, careful reconstitution, and minimized freeze–thaw exposure. When handled according to standard peptide laboratory protocols, the blend maintains structural integrity and solubility suitable for in vitro and analytical research applications.
Frequently Asked Questions
What is the Semax + Selank blend?
It is a dual-peptide research formulation supplying Semax and Selank together in a single lyophilized vial at 10 mg of each peptide. Semax is a synthetic analog of the ACTH(4-7) fragment and Selank is a synthetic analog of the immune peptide tuftsin; both carry a Pro-Gly-Pro tail that improves their stability.
Why combine Semax and Selank?
The two peptides are frequently studied together because their reported activity profiles address different aspects of the same system. Semax is an ACTH(4-7) analog and Selank is a tuftsin analog; they are distinct sequences supplied together in a fixed ratio. Supplying them in a fixed ratio lets researchers evaluate the combination under controlled conditions rather than reconstituting and dosing two vials separately.
Is this a single peptide?
No. This is a multi-peptide blend, not a single amino acid sequence. The vial contains two structurally distinct heptapeptides, so it has no single CAS number, molecular formula, or molecular weight. Analytical characterisation is performed per component.
How is the Semax + Selank blend supplied?
The blend is supplied as a lyophilized powder in a sealed vial containing 10 mg of Semax and 10 mg of Selank, for 20 mg of total peptide content. Vials ship without diluent; reconstitution with sterile water, or PBS is performed by the receiving laboratory.
How should unreconstituted blend vials be stored?
Store sealed vials at –20°C to –80°C in a desiccated environment, protected from light and moisture. Under these conditions the lyophilized material is stable for extended periods. Avoid storing vials at room temperature for longer than is necessary for handling.
How should reconstituted blend solutions be handled and stored?
After reconstitution, store at 4°C for short-term use of up to seven days, or divide into single-use aliquots and store at –20°C for longer periods. Repeated freeze–thaw cycles should be avoided, as they degrade multi-component preparations faster than single-peptide solutions.
Does this blend require a Certificate of Analysis (COA)?
Yes. Each production lot is analysed by an independent third-party laboratory, with HPLC used to verify purity of ≥99% and mass spectrometry used to confirm the identity of both components. A lot-specific COA is generated for every batch and is available for the exact lot supplied.
Is the Semax + Selank blend FDA-approved?
No. This blend is not approved by the FDA or any comparable regulatory authority for human or veterinary use. It is sold strictly for research and educational purposes and is not intended to diagnose, treat, cure, or prevent any disease.
Research Background
For a referenced comparison of these two peptides — siblings from the same institute, sharing a stabilising tail but built from different parent molecules — see Semax vs Selank: What Is the Difference?. It cites peer-reviewed sources and contains no dosing guidance.
This product is not for human consumption. It is sold strictly for research and educational purposes and is not intended to diagnose, treat, cure, or prevent any disease.
Any clinical data or research information referenced on this page is derived from peer-reviewed scientific literature and official publications. This information is provided for educational reference only and does not constitute medical advice or product claims.
By purchasing this product, you acknowledge that you are a qualified researcher and agree to use it in full compliance with all applicable laws and regulations.


