Selank

The starting point for Selank is not a hormone or a growth factor. It is tuftsin, a four-residue peptide (Thr-Lys-Pro-Arg) that Najjar and Nishioka first isolated from the heavy chain of IgG in 1970 and described as an endogenous immunomodulator. Decades later, researchers at the Institute of Molecular Genetics in Moscow asked whether the same fragment could be made stable enough in plasma to study its behavioural effects in vivo. Their answer was to add a Pro-Gly-Pro tail, producing the heptapeptide Thr-Lys-Pro-Arg-Pro-Gly-Pro that the literature now calls Selank. The structural trick is the same one used to stabilise Semax, but the parent peptide and the receptor pharmacology that come out the other end are different animals.

Where Selank parts ways with its better-known cousin

Both peptides share the Pro-Gly-Pro stabilising motif, and both came out of the same Moscow institute. That is roughly where the overlap ends. Semax is built on ACTH(4-7) and most of its published work sits in BDNF, TrkB, and ischaemia models. Selank is built on tuftsin, and most of its published work sits in GABAergic anxiolysis and enkephalin metabolism. In several rodent assays it has been compared head to head with classical benzodiazepines such as diazepam, medazepam, and phenazepam, and that comparison is part of why the compound is interesting to laboratories studying anxiety-related circuits without the sedative profile that the benzodiazepine class carries.

The tuftsin lineage matters

Because the active core was originally an immunopeptide, a slice of the Selank literature looks at things that pure neuropeptides do not usually touch. Published rodent and ex vivo work has examined effects on IL-6, on T-cell behaviour, and on gene expression panels covering both neurotransmission and immune signalling. That dual identity (a peptide with measurable behaviour in both stress assays and immune readouts) is the angle that distinguishes Selank from purely nootropic or purely immunomodulatory research peptides.

What you receive per lot

• Sealed glass vial of lyophilised Selank, inert-gas flushed before crimp sealing
• Batch-specific Certificate of Analysis with the HPLC chromatogram and mass-spec trace for that exact lot
• Lot number printed on the label and matched to the CoA

Our incoming lots run at 98 percent or better by reverse-phase HPLC, with mass spec confirming the TKPRPGP sequence to within 1 Da of the expected 751.9 g/mol. If a vial does not match its CoA on arrival, we refund it. That policy is genuine and the inbox behind it is read by a human.

Where the material comes from

We source Selank from UK and EU contract peptide manufacturers we have audited. The reason we do not list it from unverified Asian suppliers is unromantic: the silent failure mode at that end of the market is counter-ion drift and the occasional misidentified sequence, both of which corrupt assay results before anyone notices. UK orders placed Monday to Thursday afternoon ship the same working day, and roughly nine in ten arrive inside 48 hours.

Bench notes for handling

Lyophilised Selank is stable through normal transit at ambient temperature but should move to minus 20 C on arrival for any storage beyond a week. After reconstitution in bacteriostatic water, most labs refrigerate and use within two to three weeks where peptide integrity is load-bearing for the readout. For multi-arm protocols or longer time-courses needing ten or more vials, message support for a bulk quote rather than working through the cart. Live chat is staffed by people during UK working hours, and reconstitution or CoA questions reach someone who handles the actual stock.

Sold strictly for in vitro laboratory research. Not for human or veterinary use. UK 18+.