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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Spadin-derived heptapeptide; selective TREK-1 channel antagonist
Overview
PE-22-28, also called Mini-Spadin, belongs to the class of short bioactive peptide fragments: a seven-residue sequence Gly-Val-Ser-Trp-Gly-Leu-Arg (GVSWGLR) mapping to positions 22 through 28 of spadin, itself a propeptide fragment (PE 12-28) liberated during sortilin (NTSR3) maturation. Functionally it is a high-affinity, selective antagonist of the TREK-1 (TWIK-related) two-pore-domain potassium channel, reported with an IC50 near 0.12 nM — more than 300-fold above full-length spadin, whose IC50 sits around 40 nM. This makes it a compact molecular probe of TREK-1-linked neuronal signaling. Lyochem supplies PE-22-28 as a lyophilized reference standard at ≥99.0% HPLC, each lot accompanied by a Certificate of Analysis. Sequence-consistent identity is established by RP-HPLC purity profiling alongside ESI-MS mass confirmation of the Gly-Val-Ser-Trp-Gly-Leu-Arg heptapeptide against its C35H55N11O9 composition (~773.89 Da); reported counter-ion salt and residual-water figures let researchers back-calculate net peptide content. The characterization set supports use as an identity and quantitation benchmark in ion-channel pharmacology assays.
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.
Biotech R&D Groups
Preclinical biotech and pharmaceutical discovery teams sourcing characterized peptides for receptor-pharmacology, screening, and method-development campaigns.
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
This PE-22-28 standard is provided by Lyochem strictly for in-vitro laboratory investigation. It is unapproved for any clinical, diagnostic, or in-vivo human or veterinary application and must be confined to controlled research environments.
Selected literature
Frequently asked questions
Each lot is profiled by RP-HPLC and verified by ESI-MS, where the observed mass matches the C35H55N11O9 composition (~773.89 Da) expected for Gly-Val-Ser-Trp-Gly-Leu-Arg. Both the purity trace and the mass result are recorded on the Certificate of Analysis.
Keep the lyophilized powder desiccated at low temperature as noted on the COA, and equilibrate a sealed vial to room temperature before opening to limit moisture uptake. Because the tryptophan-containing sequence can be light-sensitive, prepare working solutions promptly and minimize prolonged light exposure.
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