Storing
and handling lyophilized peptides

Follow the supplier’s documented, material-specific storage and stability requirements. Cold, dry, light-protected storage is common laboratory practice, but no universal temperature or shelf life applies. Before opening a cold vial, let it reach room temperature in a desiccator or on the bench, so moisture doesn’t condense on the hygroscopic powder.

CCysteineMMethionineWTryptophan

Oxidize readily. Minimize air exposure, and consider purging vials with nitrogen or argon.

NAsparagineQGlutamine

Can deamidate, and N-terminal glutamine can cyclize, especially in solution.

Start with high-purity (distilled or deionized) water. If the peptide doesn’t dissolve, its charge and hydropathy suggest what to try next:

Net positive charge

Often dissolves better in dilute acetic acid.

Net negative charge

Often dissolves better in a dilute basic buffer, such as ammonium bicarbonate; avoid basic solutions for peptides that contain cysteine.

Very hydrophobic

Dissolve it first in a little organic solvent, such as DMSO, then dilute. Use DMF instead for peptides with cysteine or methionine, which DMSO can oxidize.

Sequence Studio shows each peptide’s charge and hydropathy to help you choose.

Solution stability depends on the peptide, solvent, concentration and storage conditions. Use a validated laboratory protocol; only freeze or aliquot where appropriate for that material. Avoid unsupported expiry claims.