Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro (TKPRPGP).[1][9] It was built on tuftsin, a natural tetrapeptide (Thr-Lys-Pro-Arg) of the immune system, with a Pro-Gly...
Certificate of Analysis included with every order.
Technical Specifications
Purity
≥98%
Form
Lyophilized powder
Storage
-20°C
Molecular Weight
751.9 g/mol
Sequence
Thr-Lys-Pro-Arg-Pro-Gly-Pro
CAS Number
129954-34-3
About Selank
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro (TKPRPGP).[1][9] It was built on tuftsin, a natural tetrapeptide (Thr-Lys-Pro-Arg) of the immune system, with a Pro-Gly-Pro tail added to the C-terminus.[4][5] Pepitiva supplies Selank as a lyophilized powder (5 mg vials, ≥98% purity) for in vitro and preclinical research.
Almost all published work on Selank was carried out at Russian institutes, mainly the Institute of Molecular Genetics of the Russian Academy of Sciences and the Zakusov Research Institute of Pharmacology,[1][2][4] and part of it was published only in Russian.[6] Independent replication outside Russia is scarce. A 2021 review by U.S. pharmacists described Selank as a poorly studied Russian drug.[8]
For research use only. Not for human consumption.
Quality & Storage
≥98% purity. Lyophilized powder. Storage: -20°C. For research purposes only.
Mechanism of Action
Proposed mechanisms
GABA-A receptor modulation: in radioligand binding experiments on brain membranes, Selank behaved as a positive allosteric modulator of [3H]GABA binding, and it changed the modulatory effect of diazepam and olanzapine.[1]
Gene expression in the GABA system: in the rat frontal cortex, Selank changed the expression of 45 of 84 neurotransmission-related genes one hour after administration, with a profile that correlated with the changes caused by GABA itself.[2]
Enkephalin-degrading enzymes: Selank inhibited the breakdown of enkephalin in human plasma in a concentration-dependent way (IC50 15 µM), and was more potent than the peptidase inhibitors bacitracin and puromycin.[3]
BDNF: in rats given ethanol for 30 weeks, Selank prevented the ethanol-induced rise of brain-derived neurotrophic factor in the hippocampus and frontal cortex.[4]
Immune genes: in mouse spleen, Selank and its short fragment Gly-Pro changed the expression of the inflammation-related genes C3, Casp1, Il2rg and Xcr1, with largely overlapping profiles.[5]
These mechanisms come mostly from animal and in vitro studies by a small number of research groups.
Research Applications
Preclinical findings
Memory in an alcohol model: in rats, Selank prevented memory and attention deficits that developed during alcohol withdrawal, measured in an object recognition test.[4]
Anxiety-related pharmacology: the binding and gene-expression data above have been used to compare Selank with benzodiazepines.[1][2]
Human data
A Russian-language comparative study in 60 patients with anxiety and somatoform disorders reported an anxiolytic effect of Selank against the benzodiazepine phenazepam.[6] This is a small study published in Russian, and larger independent trials have not been published. A Belgian medicines-control laboratory that identified Selank in seized products noted that, to its knowledge, it had not completed clinical trials.[7]
Laboratory research applications
GABAergic signaling: receptor binding and gene-expression studies.
Analytical method development: LC-MS/MS identification of nootropic research peptides.[7]
Comparison studies: with the related glyproline-family peptide Semax, and with other neuropeptides such as DSIP.
Selank is not approved by the FDA or the European Medicines Agency.[7][8] This product is sold for laboratory research only.
Storage & Handling Guidelines
Proper storage and handling are essential to maintain peptide integrity and ensure reliable research results. All Pepitiva Biolabs peptides are supplied as lyophilized (freeze-dried) powder, which provides excellent long-term stability when stored correctly. Store lyophilized peptides at -20°C for long-term storage or 2-8°C for short-term use. Once reconstituted, peptide solutions should be stored at 2-8°C and used within the timeframe specified in the product documentation. Always use sterile bacteriostatic water for reconstitution and handle peptides in a clean laboratory environment to prevent contamination. Avoid repeated freeze-thaw cycles, as thermal stress can cause peptide degradation and loss of biological activity.
Quality Control & Certification
This product is manufactured under strict quality control protocols and has been verified through comprehensive analytical testing. Each batch undergoes reverse-phase HPLC analysis for purity determination and electrospray ionization mass spectrometry (ESI-MS) for molecular identity confirmation. A detailed Certificate of Analysis (COA) is available for download, documenting purity percentage, molecular weight verification, appearance, and recommended storage conditions. Pepitiva Biolabs maintains batch-level traceability from synthesis through delivery, ensuring complete transparency and quality assurance for your research.
Frequently Asked Questions
What is Selank?
A synthetic 7-amino-acid peptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro) based on tuftsin, a natural immune-system tetrapeptide, extended with a Pro-Gly-Pro sequence.
What is the Selank mechanism of action?
Proposed mechanisms from Russian laboratory studies include allosteric modulation of GABA-A receptor binding, inhibition of enkephalin-degrading enzymes and effects on BDNF. These come mainly from animal and in vitro work.
Is Selank approved in the US?
No. Selank is not approved by the FDA. Most research on it comes from Russia, and independent clinical trials have not been published.
What is the difference between Selank and Semax?
Both are synthetic heptapeptides ending in Pro-Gly-Pro developed in Russia. Selank is based on tuftsin (an immune peptide); Semax is based on a fragment of ACTH. See Semax.
What is the molecular weight of Selank?
751.9 g/mol (formula C33H57N11O9), CAS 129954-34-3, according to PubChem.
How should Selank be stored?
Keep the lyophilized powder at −20 °C, protected from light and moisture.
Is this product approved for human use?
No. This product is intended exclusively for in vitro scientific research and laboratory use. It is not approved for human or veterinary use, not intended for diagnostic or therapeutic purposes, and should not be administered to humans or animals under any circumstances.
How do I reconstitute this peptide?
Add sterile bacteriostatic water slowly to the vial, directing the stream against the glass wall rather than directly onto the lyophilized powder. Gently swirl the vial until the powder is fully dissolved — do not shake vigorously. The recommended reconstitution volume depends on your desired concentration. Refer to the product documentation for specific guidance.
Can I get a Certificate of Analysis (COA)?
Yes. A Certificate of Analysis is included with every order and is also available for download from the product page. The COA documents HPLC purity, mass spectrometry identity confirmation, batch number, production date, and storage recommendations.
Scientific References
Vyunova TV, Andreeva L, Shevchenko K, et al. Peptide-based Anxiolytics: The Molecular Aspects of Heptapeptide Selank Biological Activity. Protein Pept Lett. 2018;25(10):914-923. PubMed
Volkova A, Shadrina M, Kolomin T, et al. Selank Administration Affects the Expression of Some Genes Involved in GABAergic Neurotransmission. Front Pharmacol. 2016;7:31. PubMed
Zozulya AA, Kost NV, Yu Sokolov O, et al. The inhibitory effect of Selank on enkephalin-degrading enzymes as a possible mechanism of its anxiolytic activity. Bull Exp Biol Med. 2001;131(4):315-317. PubMed
Kolik LG, Nadorova AV, Antipova TA, et al. Selank, Peptide Analogue of Tuftsin, Protects Against Ethanol-Induced Memory Impairment by Regulating of BDNF Content in the Hippocampus and Prefrontal Cortex in Rats. Bull Exp Biol Med. 2019;167(5):641-644. PubMed
Kolomin T, Morozova M, Volkova A, et al. The temporary dynamics of inflammation-related genes expression under tuftsin analog Selank action. Mol Immunol. 2014;58(1):50-55. PubMed
Medvedev VE, Tereshchenko ON, Israelian AIu, et al. [A comparison of the anxiolytic effect and tolerability of selank and phenazepam in the treatment of anxiety disorders]. Zh Nevrol Psikhiatr Im S S Korsakova. 2014;114(7):17-22. PubMed
Vanhee C, Francotte A, Janvier S, et al. The occurrence of putative cognitive enhancing research peptides in seized pharmaceutical preparations: An incentive for controlling agencies to prepare for future encounters of the kind. Drug Test Anal. 2020;12(3):371-381. PubMed
Doyno CR, White CM. Sedative-Hypnotic Agents That Impact Gamma-Aminobutyric Acid Receptors: Focus on Flunitrazepam, Gamma-Hydroxybutyric Acid, Phenibut, and Selank. J Clin Pharmacol. 2021;61 Suppl 2:S114-S128. PubMed
PubChem. Selank, CID 11765600: C33H57N11O9, 751.9 g/mol; CAS 129954-34-3. Source
Sources are peer-reviewed publications indexed in PubMed and trial registrations on ClinicalTrials.gov. Each citation was checked against its PubMed record.
For research use only. Not for human consumption.
Related Peptides
≥98%
Neuropeptide
Semax
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro (MEHFPGP).[1][7] It ...
