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 immunomodulatory 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.
Research Applications
Cognitive and Neurotrophic Signalling Research
This blend is used as a research formulation for studying neurotrophic support and learning-related processes. Laboratory investigations focus on its role in:
- Neurotrophic Factor Expression: Evaluation of BDNF and NGF expression in neuronal culture and hippocampal tissue models
- Synaptic Plasticity: Analysis of long-term potentiation and dendritic remodelling
- Memory Consolidation Models: Examination of acquisition and retention in behavioural paradigms
- Neuronal Survival: Investigation of resilience to excitotoxic and hypoxic challenge
Experimental protocols commonly utilise primary neuronal cultures, hippocampal slice preparations, and rodent behavioural models to characterise the combined response.
Stress Response and Anxiolytic Research
Selank contributes the anxiolytic-facing side of this blend, and the pairing is studied for its effects on stress-response systems. Laboratory investigations focus on its role in:
- GABAergic Signalling: Analysis of GABA receptor expression and inhibitory tone
- HPA Axis Regulation: Examination of corticosterone response under controlled stressors
- Anxiety-Related Behaviour: Evaluation in elevated plus maze and open field paradigms
- Enkephalin Degradation: Research into enkephalinase activity and endogenous peptide half-life
These studies typically combine behavioural endpoints with receptor binding and gene expression assays to separate acute from sustained effects.
Monoamine and Neurotransmitter Research
Both components have been examined for their influence on monoaminergic systems, making the blend a subject of neurotransmitter research. Laboratory investigations focus on its role in:
- Dopaminergic Tone: Study of dopamine turnover and receptor sensitivity in striatal tissue
- Serotonergic Signalling: Analysis of serotonin metabolism and transporter expression
- Noradrenergic Activity: Examination of norepinephrine release under stimulated conditions
- Attention and Arousal Models: Investigation of vigilance-related behavioural readouts
Microdialysis, HPLC quantification of tissue monoamine content, and receptor autoradiography are commonly applied in this line of work.
Neuroimmune and Cytokine Modulation Research
Selank’s tuftsin lineage gives this blend a documented neuroimmune dimension. Laboratory investigations focus on its role in:
- Cytokine Profiling: Measurement of interleukin and interferon expression in stimulated immune cells
- Neuroinflammation Models: Examination of microglial activation states
- Immune-Brain Crosstalk: Analysis of peripheral immune signalling and central response
- Stress-Immune Interaction: Research into immune parameters under chronic stress conditions
Protocols frequently pair in vitro immune cell assays with in vivo models to characterise both peripheral and central components of the response.
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.
What is this blend commonly researched for?
Research on this pairing centres on central nervous system signalling. Common areas include:
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Neurotrophic factor expression, particularly BDNF and NGF
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Stress-response regulation and anxiolytic-related behavioural endpoints
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Monoamine neurotransmission, including dopaminergic and serotonergic systems
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Neuroimmune signalling and cytokine profiles
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 more often associated with neurotrophic and attention-related endpoints, while Selank is more often associated with anxiolytic and neuroimmune endpoints. 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 bacteriostatic water, 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.


