PE-22-28

PE-22-28 is a seven-residue peptide derived from spadin — the natural fragment released from the propeptide of the sortilin/neurotensin-receptor-3 precursor — corresponding to residues 22–28 of that fragment. Investigators study it as a structurally defined research material in neuroscience models focused on the TREK-1 (KCNK2) two-pore-domain potassium channel, the documented molecular point of interest for spadin-class peptides. The peer-reviewed literature catalogs spadin and its shortened analogs in TREK-1 channel-blockade research and in structure-activity work identifying the minimal active fragment. Its molecular identity is fixed by structural confirmation against PubChem CID 165437303, empirical formula C35H55N11O9. Supplied for laboratory characterization and in-vitro channel-signaling studies only. For research use only; not for human consumption, medical use, or veterinary application.

PE-22-28 is a short linear heptapeptide representing the minimal active region of spadin identified in the published literature. Spadin-class peptides are documented as inhibitors of the TREK-1 (KCNK2) two-pore-domain potassium channel, a background K+ channel implicated in neuronal-excitability research; the literature describes the shortened PE-22-28 fragment as retaining the channel-interaction profile of the parent spadin with improved stability characteristics for research use. Because the documented point of interaction is an ion channel rather than a GPCR, the interaction profile is framed in terms of channel-current modulation in electrophysiology research. Pharmacokinetic descriptors documented in published investigations reflect the improved stability reported for the fragment relative to full-length spadin. All activity descriptors here are framed as documented in published research rather than as effects of the supplied product. Structural confirmation is established by mass spectrometry and HPLC-validated purity on each Certificate of Analysis.

Experimental domains documented in the published literature include TREK-1 (KCNK2) channel-current electrophysiology assays, neuronal-excitability research in cell-culture and animal-model contexts, comparative structure-activity work identifying the minimal active spadin fragment, and mood-and-neuroplasticity research paradigms where TREK-1 modulation is the experimental variable. Investigators use PE-22-28 research material as a defined TREK-1-interacting peptide reference. Use in laboratory research extends to mechanism-elucidation paradigms probing background-potassium-channel signaling. The reference standard is supplied for these and equivalent in-vitro and animal-model experimental contexts only, with no associated guidance for human, clinical, or veterinary use.

Each lot is characterized by reverse-phase HPLC for chromatographic purity and by mass spectrometry for molecular-ion confirmation against the C35H55N11O9 empirical formula. Purity is reported as an HPLC-area percentage on the Certificate of Analysis distributed with every lot, alongside the molecular-weight match within instrument tolerance. Peptide content where applicable is determined by amino-acid analysis or nitrogen-content assay following the analytical method specified on the COA. Residual solvent and water content are reported categorically when these parameters are part of the lot release specification. The COA records the lot identifier, manufacturing date, and analytical method versions used, providing a traceable provenance chain from synthesis through release. Researchers requiring batch-level analytical detail should reference the COA distributed with the supplied material.

For laboratory storage, the lyophilized reference standard should be held at −20°C in its sealed, light-protected container until ready for analytical use. Allow vials to equilibrate to ambient temperature before opening to avoid moisture condensation on the lyophile. Reconstitution for in-vitro experimental use is typically performed in bacteriostatic water or a researcher-selected buffer compatible with the downstream assay; once reconstituted, store the working solution at 2–8°C and characterize stability in the relevant buffer prior to extended storage. Avoid repeated freeze-thaw cycles of reconstituted material — single-use aliquots are preferred where peptide integrity is assay-critical. These handling parameters reflect general best-practice for lyophilized peptide reference standards and do not constitute preparation guidance for human or veterinary use.