We report net peptide content, not just purity — so the milligrams you dose aren't padded with water and counter-ion. RP-HPLC purity and ESI-MS identity, on a lot-numbered COA.
Net peptide content, not just purity — RP-HPLC + ESI-MS, lot-numbered COA.
Net peptide content on every lot's COA.
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Tuftsin analog · anxiolytic research peptide
Lyochem primary owner
This Lyochem page is the primary SEO owner for research labs, CROs, and method-development teams qualifying Selank as a documented research-standard lot. The page should answer whether the buyer can review HPLC purity, identity confirmation, lot continuity, stability handling, and assay-fit documentation before ordering.
Overview
Built from the immunomodulatory tetrapeptide Tuftsin and capped with a protease-resistant Pro-Gly-Pro extension, Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. Its proposed activity involves GABAergic modulation together with effects on enkephalin turnover, and because this occurs without the sedation or dependence seen with benzodiazepines, it underlies the anxiolytic research interest surrounding the peptide. Created alongside Semax at Moscow's Institute of Molecular Genetics, Selank carries prescription approval in Russia for generalized anxiety disorder and is studied for anxiolytic, cognitive, and mood-related outcomes. Lyochem supplies Selank acetate as a lyophilized reference standard at ≥99.0% HPLC, with each lot released against RP-HPLC purity, ESI-MS identity, water content, and acetate counter-ion determination. As with Semax, intranasal dosing dominates the published record because systemic administration crosses the blood-brain barrier poorly; isotonic reconstitution vehicles are advised, and preservatives that react with short peptides should be left out. Fill sizes of 5 mg and 10 mg suit most bench workflows, and LAL endotoxin plus microbial-limits testing can be added for in vivo applications.
Applications & buyer fit
Cognitive and neuropeptide buyers are predominantly research labs running in vivo rodent studies. The dominant administration route in the published literature is intranasal — Semax, Selank, DSIP, Pinealon — because these peptides are not meaningfully blood-brain-barrier permeable when delivered systemically. For in vivo workflows, endotoxin and microbial-limit testing is recommended at the CoA stage so the bioassay readout is not confounded by contamination unrelated to the test article.
Academic Laboratories
Universities, medical schools, and government research institutes qualifying a reference standard for a method-development or in vivo workflow.
Every release ships with its own batch-specific CoA — identity, purity, and the analytical scope agreed at quote stage, tied to the exact lot you receive.
Review a representative batch CoA before you order, so you can confirm the packet matches what your method or sponsor audit needs.
Supplied strictly as a research reagent to research institutions — not a finished dosage form and not for human administration. Buyer qualification runs at the inquiry stage.
Specifications
Documentation available on request
Regulatory note
In Russia this is an approved prescription medication for generalized anxiety disorder; it remains unapproved across the US and EU. Outside Russia, it is sold for research use only.
Selected literature
Frequently asked questions
The two heptapeptides carry the same C-terminal stabilization tripeptide but differ across the N-terminal region, so the discriminating data lie in mass and sequence, not the shared motif. ESI-MS gives distinct intact masses because the differing residues change the total formula, and RP-HPLC retention differs under a fixed method since the N-terminal composition alters hydrophobicity. Where confirmation must be unambiguous, LC-MS/MS fragmentation reads the residue ladder and assigns the Tuftsin-derived sequence rather than the ACTH-derived one. We report the measured mass, purity, and chromatographic behavior per lot so a qualifying lab confirms it received Selank specifically.
For a synthetic heptapeptide the RP-HPLC trace is the primary purity document. The main-peak area gives the reported figure, while the resolved minor peaks correspond to synthesis-related species such as deletion or incompletely deprotected sequences; their positions and relative sizes form part of the lot record. Because these related impurities can share a similar mass to the target, chromatographic separation rather than mass alone is what quantifies them. We transcribe the actual purity value and the chromatogram onto the certificate for the specific batch, so a receiving lab has a documented impurity profile to reference in its own method qualification.