Storage and Handling of Peptides

Store peptides long term as lyophilized powders in a desiccator at -20°C. Peptides may be stored 3 months to 5 years.

Peptides may be stored short term in a frozen solution at -20°C or as a refrigerated lyophilized powder. Peptides can be stored up to 3 months in these conditions.

Before opening or weighing peptides, place the vials in a desiccator and allow the vials to warm to room temperature.

Acidic peptides dissolve best in a basic buffer, basic peptides are best dissolved in acidic buffer.

Peptides that contain cysteine, methionine, or tryptophan are sensitive to oxidation. Before dissolving these peptides, degas the buffer under reduced pressure to remove oxygen.

A small amount of dimethylformamide (DMF) or dimethylsulfoxide (DMSO) can be added to the buffer if the peptide is very hydrophobic. If DMSO is used, the peptide solution should not be stored.

Use peptide solutions immediately to avoid degradation. Unused portions may be frozen in aliquots and stored short term at -20 °C if the pH of the solution is between pH 5-7. For long tern storage, lyophilize the peptide solutions and store the dry powders at -20 °C in sealed vials within a desiccator.

Avoid unnecessary thaw-freeze cycles of peptide solutions. Do not store frozen peptide solutions in a frost-free freezer.

For maximum stability, re-lyophilize unused peptide solutions.