Semax specifications and molecular characteristics
The technical specification for Semax, the Semax research material supplied by Semax Research Supply: molecular formula C37H51N9O10S, average molecular weight 813.93 g/mol, 7 residues, supplied as a white lyophilized powder. Each item is explained below.
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Specification table
| Product | Semax |
|---|---|
| Type | Synthetic heptapeptide |
| Molecular formula | C37H51N9O10S |
| Molecular weight | 813.93 g/mol (average) |
| Length | 7 residues |
| Sequence | MEHFPGP |
| N-terminus | Free amine (Met1) |
| C-terminus | Free acid (Pro7) |
| Form | White lyophilized powder |
| Vial sizes | 10 mg |
| Purity specification | ≥95% (HPLC-UV) |
| Purity, current lots | 99.84% |
| Identity specification | Confirmed by LC-MS |
| Testing laboratory | Freedom Diagnostics (independent) |
| Storage | Store sealed, dry and protected from light at the temperature stated on the vial label. Allow a cold vial to reach room temperature before opening. |
| Designation | Research use only |
Current lot results against specification
Every current lot meets the release specification. Current lots test at 99.84% by HPLC-UV against a specification of ≥95%, and identity is confirmed by LC-MS on every lot.
Semax molecular formula
The molecular formula of Semax is C37H51N9O10S. Calculated for the free peptide (C-terminal acid), not including counterions.
Semax molecular weight
The average molecular weight of Semax is 813.93 g/mol. "Average" means it is calculated from natural isotope abundances, which is the value used to predict the ions seen in LC-MS. With this weight, Semax is expected at m/z 814.9 with one charge and m/z 408.0 with two charges.
Semax sequence
MEHFPGP
Positions 1–4 (MEHF) correspond to ACTH(4–7); positions 5–7 (PGP) are the added extension.
Structure and modifications
Semax is linear with a free N-terminus (Met1) and free C-terminal acid (Pro7). Methionine 1 is the residue most sensitive to oxidation, which adds 16 Da per oxygen and is one of the changes LC-MS can detect. The molecule contains no cysteine or tryptophan.
Physical form
White lyophilized powder, recorded as the appearance on every certificate. Lyophilization (freeze-drying) removes water, which slows most chemical degradation. What lyophilized means.
Purity and identity specifications
Semax Research Supply’s stated release specification is ≥95% HPLC-UV purity with identity confirmed by LC-MS. The current lot, KB29412, reported 99.84%. How purity is measured, or how specifications fit into the quality and supply-chain process.
Analytical and testing methods
HPLC-UV for purity, LC-MS for identity and laboratory quantitation for net content, performed on every lot by Freedom Diagnostics. LAL endotoxin testing (USP <85>) and PCR microbial screening are reported for lots where they were run. Testing and quality control.
Research designation
Semax is designated research use only: supplied for laboratory research by qualified personnel. Research use only policy.
Buy Semax
10 mg vials. Current lot KB29412 tested at 99.84% purity with identity confirmed by LC-MS. Current purchasing is available through Klow.bio.