The heptapeptide structure, the Pro-Gly-Pro tail, solubility and storage considerations for Semax as a standard.
Heptapeptide structure
Semax is a seven-residue peptide based on the ACTH(4-10) sequence and capped with a Pro-Gly-Pro tail. The proline-rich terminus imposes conformational constraints on the backbone and is widely noted as contributing to the analog's relative stability against peptidase activity in research conditions.
Composition and mass
With a molecular weight near 813.9 g/mol, Semax is a compact peptide whose calculated mass serves as the reference point for mass-spectrometric identity checks. The observed mass of a reagent lot is matched against this value to confirm assignment during characterization.
Solubility for benchwork
As a small, water-compatible peptide, Semax is generally prepared in aqueous laboratory media for making standards and chromatography samples. Solubility notes here apply only to analytical sample preparation, and gentle handling preserves the integrity of the reference material.
Stability and storage
The lyophilized solid is best stored cold, dry and away from light to limit hydrolytic and oxidative changes. Working solutions are treated as short-lived, kept cold, and protected from repeated freeze-thaw cycles. The proline-containing terminus contributes to stability but does not replace good custodianship of the standard.