Good peptide storage protects your results. A lyophilized peptide can stay stable for a long time, but heat, moisture, oxygen and light all speed up degradation once a vial leaves the freezer. This guide covers practical peptide handling for the laboratory: how to store lyophilized peptides, how to open vials without introducing water, and why solutions need extra care.
Why peptides are supplied lyophilized
Lyophilization, or freeze-drying, removes water from the peptide under vacuum. Water drives hydrolysis and many other degradation reactions, so a dry, sealed powder is far more stable than the same peptide in solution. That is why research peptides, including every vial in our research peptides collection, are shipped as lyophilized powders.
Temperature: cold and constant
For long-term storage, Bachem’s handling and storage guidelines recommend keeping lyophilized peptides in a tightly closed container below −15 °C, with lower temperatures preferred. In practice many laboratories use −20 °C freezers, and −80 °C for material they plan to keep for an extended period. For shorter periods, follow the storage condition on the product’s specification table or certificate of analysis; on our product pages this is listed in the Storage row.
Stability also depends on keeping the temperature constant. Avoid frost-free freezers that cycle through warming phases, and keep frequently used vials separate from long-term stock so the stock is not repeatedly exposed to room temperature.
Moisture: let the vial warm before opening
Many peptides are hygroscopic, meaning they pull water out of the air. If you open a cold vial straight from the freezer, moisture condenses on the powder. Bachem’s guidance is to let the container reach room temperature, ideally in a desiccator, before opening it, then weigh out what you need quickly and reseal the vial tightly. Peptides rich in residues such as aspartic acid, glutamic acid, lysine, arginine and histidine are especially prone to taking up water.
Oxidation and light
Peptides that contain cysteine, methionine or tryptophan are sensitive to oxidation. For these sequences, minimise the time the vial is open and consider flushing the headspace with an inert gas such as nitrogen or argon before resealing. Store vials away from bright light, for example in their outer packaging or an opaque box.
Peptides in solution need extra care
Peptides are much less stable in solution than as dry powders, so avoid storing solutions for long periods. When you do need a stock solution for experiments:
- Prepare only the amount you need, using appropriate sterile, high-purity solvents or buffers.
- Divide the solution into single-use aliquots so each tube is thawed only once.
- Freeze aliquots promptly and avoid repeated freeze-thaw cycles, which can promote aggregation and degradation.
- Label every aliquot with the peptide name, lot number, concentration, solvent and date.
A peptide storage checklist
- Store lyophilized peptides sealed, dry, cold and dark.
- Check the storage condition on the product specification table and COA.
- Warm vials to room temperature in a desiccator before opening.
- Reseal quickly; use inert gas for oxidation-sensitive sequences.
- Aliquot solutions and avoid freeze-thaw cycles.
- Record lot numbers so results can be traced back to the matching certificate of analysis.
Find storage details for each product
Every product page at Protides Health includes a Storage row in its specification table, alongside the appearance, solubility and molecular data. Browse the shop or explore peptide blends and bioregulator peptides to compare products.
Sources
Research use only. Products sold by Protides Health are intended for laboratory research and are not for human or veterinary consumption. This article is educational and is not medical advice.