Lyophilised (freeze-dried) peptides are supplied as a dry powder or "cake" in a sealed vial. This guide explains what that powder is, why moisture, light and air matter to it, and the general lab practice for keeping it in good condition. It covers the dry powder only. It isn't a guide to preparing or using any material, and we don't provide preparation or usage instructions of any kind.
What lyophilised powder is
Lyophilisation, or freeze-drying, removes water from a material by freezing it and then drawing the ice off as vapour under low pressure, without passing through a liquid stage. What's left is a light, porous solid with most of its water removed. That solid is what you see in the vial: sometimes a compact cake, sometimes a loose powder, and sometimes a mixture of both after transport. The appearance alone doesn't tell you anything about the material's condition.
With most of the water gone, a dry powder is generally far more stable than the same material would be in any other form. But "more stable" isn't the same as "unaffected". The same porous structure that makes freeze-drying work also gives the powder a large surface area, so it can readily take up moisture from the air if it's left open.
The central rule
Storage conditions differ from one material to the next, and each material's stated storage conditions come first. General lab practice for dry powders: keep containers sealed and away from light, store them somewhere dry with a desiccant, and reseal promptly after a check.
Everything below explains the reasons behind that line. Where a material has its own stated storage conditions, those take priority over anything general in this guide.
Moisture
Moisture is the main concern for any dry powder. Many peptides are hygroscopic, which means they readily take up water from the air. Water taken up by the powder can lower its stability over time, and it also changes how much of the weight in the vial is actually peptide rather than water.
General practice:
- Keep containers sealed. A closed vial is the best protection the powder has. Leave the seal intact until a check is genuinely needed.
- Store somewhere dry with a desiccant. A desiccant, such as silica gel sachets, absorbs moisture from the air inside a storage container. Many sachets change colour when they're saturated, and should then be replaced or regenerated.
- Keep checks brief. Each time a container is opened, the powder meets the surrounding air. Open containers only when necessary, and for as short a time as possible.
- Reseal promptly after a check. Close the container fully as soon as the check is done.
Light
Some amino acid residues and some metal complexes are sensitive to light, which can contribute to gradual chemical change. Keeping containers away from light removes that variable.
General practice:
- Keep containers out of direct sunlight and away from bright lab lighting.
- Use an opaque storage container or a closed cupboard or drawer.
- Amber glass or foil wrapping can give extra shielding where a material's stated conditions ask for protection from light.
Air
Oxygen in the air can react with some residues over time. Peptide handling literature commonly singles out cysteine, methionine and tryptophan as the residues most prone to oxidation. Cysteine, for example, carries a free thiol (–SH) group that can oxidise on exposure to air.
General practice:
- Keep containers closed and tightly sealed.
- Limit how often and how long they're opened.
- Some laboratories flush the headspace of a container with an inert gas, such as nitrogen or argon, before resealing. Follow your laboratory's own procedures.
Steady conditions
Moving a container repeatedly between different environments adds avoidable variation and gives moisture more chances to reach the powder. A few habits help:
- Decide where each container lives, and move it as little as possible.
- Group containers so that checking one doesn't mean disturbing the rest.
- Return each container to its storage place promptly after a check.
Labelling and records
Good records make good storage practice easier to follow. For each container, a simple log might note:
- the compound and the vial size
- the date it was received
- where it's stored
- the date of each check, and whether the container was resealed straight away
Using stock on a first-in, first-out basis keeps older material from being overlooked. If you need documents for a material, our Manufacturer COAs (SENOBIO), listed by product, where available, are on our COAs page. Our vial labels don't currently show a lot number, so a certificate may not be for the lot you receive. If you have a question about our documents, email vitaluxe@vitaluxelabs.co.uk.
A quick checklist
- Each material's stated storage conditions come first.
- Keep containers sealed.
- Keep them away from light.
- Store them somewhere dry, with a desiccant.
- Keep checks brief, and reseal promptly after each one.
- Limit exposure to air.
- Keep a simple log of what's stored, where, and when it was checked.
What this guide doesn't cover
This guide is about keeping dry, lyophilised material in good condition. It doesn't cover preparing, handling or using any material in an experiment. Those steps depend on your work and should follow your laboratory's own validated procedures. Our FAQ explains our position.
For background on the documents that accompany a material, see our guide to reading a peptide certificate of analysis. You can browse the current range in Research Peptides UK, including BPC-157, GHK-Cu and NAD+.
For laboratory research use only. Not for human or veterinary use. 18+
