Cognitive & Neuro

Peptides studied in neuroscience and cognitive research. This category covers compounds investigated for neurotrophin expression, neurotransmitter systems and sleep architecture: Semax, an ACTH(4-10) analogue studied for BDNF and NGF expression and neuroprotection; Selank, a tuftsin analogue examined in GABAergic signalling and anxiolytic models; and DSIP (delta sleep-inducing peptide), studied in sleep-architecture and neuroendocrine research.
These three share a design logic more than a mechanism. Semax and Selank are both short fragments of larger endogenous peptides extended with a Pro-Gly-Pro tail — proline’s ring constrains the backbone and is poorly accepted by many proteases, so the extension both stabilises the molecule and slows enzymatic attack. DSIP is older and stranger: isolated in the 1970s from the cerebral venous blood of rabbits in induced slow-wave sleep and named for the observation rather than a mechanism, it still has no definitively identified receptor.
Reading this literature takes some care. A large share of the primary work on Semax and Selank was published in Russian-language journals, some of it not indexed in Western databases, and independent replication outside the originating institutes is thinner than the publication count first suggests. The compounds themselves are easy to verify: at four to nine residues, coupling efficiency compounds over very few steps, so a certificate should be clean and unambiguous. Semax contains methionine, which oxidises to the sulfoxide with a +16 Da mass shift — the most common finding on a certificate for it. Our Semax and Selank comparison covers the pair in depth.
All compounds are supplied as lyophilised powder at 99%+ HPLC-verified purity, tested by an independent third-party laboratory. Certificates of Analysis available on request. For in-vitro research and laboratory use only.