Neuroprotection & Cognitive Peptide Research: Semax, Selank, DSIP, Dihexa, Adamax, Cerebrolysin, ARA-290, B12, and Dermorphin — Full B2B Lab Sourcing Guide
Research Guide | 2026-09-03 | 15 min read
Comprehensive research guide covering nine neuroscience research molecules: Semax, Selank, DSIP, ARA-290 (Cibinetide), Dihexa, Adamax, Cerebrolysin peptide fraction, B12 (research-grade reference), and Dermorphin (analytical probe). Includes melanocortin-derived nootropic biology, neurotrophic receptor pharmacology, HPLC specification ranges, and batch-level COA expectations.
Introduction: The neuroscience research-peptide cluster
The nine molecules in this guide fall into three functional clusters that map the dominant research themes in modern neuroscience:
- **Melanocortin-derived nootropics**: Semax and Adamax.
- **Innate-immune and anxiolytic peptides**: Selank and DSIP.
- **Neurotrophic and repair peptides**: Dihexa, ARA-290, Cerebrolysin.
- **Analytical reference and probe molecules**: B12 (methylation-cycle support) and Dermorphin (MOR probe).
Although each molecule hits a different receptor or pathway, they cluster together because buy-side research programs routinely source them under a single institutional procurement order and want one batch-quality dossier covering all nine. This guide is written as the documentation anchor for that pattern.
Molecular Architecture, Receptor Target, and Pharmacokinetic Profile
Semax (MC4R biased agonist, BDNF-upregulating)
Semax is a 7-amino-acid synthetic peptide (Met-Glu-His-Phe-Pro-Gly-Pro, 871.0 Da) derived from ACTH (4-10). It carries a free N-terminus and a free C-terminus (no amidation, no acetylation). The peptide is a biased MC4R agonist that activates Gs but weakly recruits β-arrestin. Semax elevates BDNF mRNA in hippocampal CA1, CA3, and dentate gyrus of rodent models within 1-4 hours of intranasal administration. Plasma half-life is ~30 minutes in rat, but central neurotrophic effects persist for several hours.
Adamax (long-acting Semax analogue)
Adamax is a Semax analogue with extended plasma stability via an N-terminal acetyl group, an additional D-Arg substitution at position 3, and a C-terminal amidation. The molecular formula and weight differ slightly from Semax; the key behavior-change is plasma half-life extension to 60-90 minutes, which makes Adamax preferable for chronic dosing paradigms. Adamax preserves Semax's BDNF-upregulating activity and its MC4R agonist effect.
Selank (CD14/TLR4-modulating, anxiolytic)
Selank is a 7-amino-acid synthetic peptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro, 752.9 Da), a Pro-Gly-Pro extension of tuftsin (TKPR). Selank modulates CD14/TLR4 signaling in microglia, which indirectly upregulates 5-HT1A receptor expression and enhances GABAergic transmission via increased GAD67 activity. The downstream behavioral effect is anxiolytic-like activity in elevated-plus-maze and light-dark-box rodent tests.
DSIP (slow-wave-sleep modulating)
DSIP is a 9-amino-acid linear peptide (Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu, 848.9 Da). Despite incomplete receptor characterization, DSIP reliably increases slow-wave-sleep duration in rodent models at 1-10 nmol/kg dosing. Its mechanism likely involves indirect modulation of NMDA-receptor subunit expression on thalamocortical neurons and interaction with somatostatin-positive thalamic reticular nucleus interneurons.
Dihexa (HGF/c-Met high-affinity agonist)
Dihexa is a 6-amino-acid hexapeptide with an N-terminal n-hexanoyl cap (often represented as n-hexanoyl-YI-Ahx-R-NH2 with a hexanoic-acid-modified N-terminus, molecular weight ~432 Da). Dihexa binds c-Met (HGF receptor) with picomolar affinity and induces receptor homodimerization. In cell-based neurite-outgrowth assays, Dihexa is active at femtomolar concentrations, exceeding BDNF in potency for synaptic protein synthesis. Its oral bioavailability in rodent models is low; subcutaneous or intracerebroventricular routes are standard.
Cerebrolysin (porcine-brain neurotrophic peptide fraction)
Cerebrolysin is a low-molecular-weight peptide fraction produced by controlled enzymatic digestion of porcine brain tissue. The fraction contains BDNF-like, GDNF-like, CNTF-like, and IGF-1-like neurotrophic peptide fragments. Cerebrolysin is therefore a peptidomix rather than a single defined molecule. Its biological characterization requires bioassay (neurite outgrowth) in addition to HPLC peptide fingerprinting.
ARA-290 / Cibinetide (Innate Repair Receptor agonist)
ARA-290 is an 11-amino-acid linear peptide (Ac-EEDVKLASAAQ-NH2, 1257.3 Da) designed to bind the innate repair receptor (IRR = EPOR + CD131 heterodimer) without signaling through the classical erythropoietic EPOR. Its research applications include small-fiber neuropathy models, ischemic tissue repair, and neuro-inflammatory modulation.
B12 / Cyanocobalamin (analytical reference)
Cyanocobalamin (C₆₃H₈₈CoN₁₄O₁₄P, 1355.4 Da) is a corrin-tetrapyrrole cobalt complex. Research use covers neuronal cell culture supplementation, homocysteine/methylation-cycle enzymatic assays, and B12-deficiency model characterization. Specifications emphasize HPLC purity ≥98% and confirmation of elemental cobalt.
Dermorphin (mu-opioid-receptor high-affinity probe)
Dermorphin is a 7-amino-acid peptide (YAFGYPS-NH2, 865.0 Da) with a D-Ala at position 2 — one of the rare D-amino-acid-containing peptides in nature. Dermorphin is a high-affinity MOR agonist with ~100-fold selectivity over delta- and kappa-opioid receptors in receptor binding studies. Research use covers opioid-receptor binding affinity assays, G-protein-coupling analysis, and receptor internalization kinetics.
Receptor Signaling Summary Table
| Peptide | Receptor | G-protein | Primary Endpoint | |---|---|---|---| | Semax | MC4R (biased) | Gs | BDNF upregulation, synaptic plasticity | | Adamax | MC4R (biased) | Gs | Chronic BDNF support | | Selank | CD14/TLR4 | (modulates) | 5-HT1A upregulation, anxiolytic-like effect | | DSIP | (putative DSIP-R, NMDA-modulatory) | — | Slow-wave sleep | | Dihexa | c-Met (HGF receptor) | — | BDNF-like synaptogenic signaling | | ARA-290 | IRR (EPOR/CD131) | — | Small-fiber repair, neuro-inflammation | | Dermorphin | mu-opioid receptor (MOR) | Gi/Go | Analgesia probe, MOR binding | | B12 | (not receptor-mediated; cofactor) | — | Methylation cycle, myelin support | | Cerebrolysin | (multi-target) | — | Multi-neurotrophic peptidomix |
Quality Specifications Buyers Should Verify
Each of these nine molecules should arrive with a batch-specific COA pack that documents:
- **HPLC purity** — ≥99% for Semax, Selank, DSIP, Dihexa, ARA-290, Adamax, Dermorphin (single-component peptides); ≥98% for Cerebrolysin (peptide fraction); ≥98% for B12 with elemental cobalt confirmation.
- **Mass spectrometry identity** — measured mass within ±1 Da of theoretical for each defined peptide.
- **Counter-ion / salt form** — acetate is dominant; trifluoroacetate should be quantified or absent.
- **Endotoxin (LAL)** — <1 EU/mg for in-vitro biological work.
- **Residual solvents** — acetonitrile and TFA residuals below ICH Q3C limits.
- **Lyophilization confirmation** — visual cake, moisture ≤5%, reconstitution note.
- **Chiral verification for Dermorphin** — the D-Ala-2 stereochemistry should be confirmed by Marfey's method or chiral LC-MS to differentiate Dermorphin from its all-L deleterious-diastereomer.
ZePeptide ships all nine molecules as lyophilized powders in 10-mg or 25-mg glass vials with the COA pack described above. Buyers sourcing the full neuroscience kit can request a single combined dossier covering all batches.
Research-Use Disclaimers
All molecules in this guide are supplied strictly for laboratory research, not for human or animal administration outside regulated research protocols. Dermorphin and other opioid-probe peptides are controlled substances in many jurisdictions; buyers should confirm institutional licensing and applicable import/export controls before ordering.
---
Research Disclaimer: This guide compiles published peer-reviewed pharmacology and analytical-chemistry references. It is intended for laboratory scientists sourcing research-grade peptides for in-vitro, ex-vivo, and animal-model studies. No content here constitutes medical or veterinary advice.
Note: All research peptides listed in this guide are intended for laboratory research purposes only and are not for human or animal consumption. Buyers are responsible for institutional approvals, DEA/EMA scheduling review, biosafety committee registration, and applicable import/export compliance for the destination country.
ZePeptide content is for lawful laboratory and in-vitro research sourcing. Products are not supplied for human or veterinary use.