Lyophilized peptide vials 5mg and 10mg are the standard formats in our catalog, and the two numbers on the label that buyers most often confuse are net content and purity. This page explains what lyophilized means, how the label and the certificate of analysis relate, and how sealed vials should be stored in the laboratory. All materials are for laboratory research use only.
Browse vial sizes and lots: /shop
What "lyophilized" means
Lyophilization is freeze-drying. A solution of the purified peptide is frozen and the water is removed by sublimation under vacuum, leaving a dry powder or cake in the vial. The result is stable for long storage when kept cold and dry, which is why research peptides are shipped this way rather than in solution.
Net content versus purity
The label states net content: 5 mg or 10 mg of material in the vial. The certificate states purity: the HPLC area percentage of the target sequence. They answer different questions. A 10 mg vial at 99% purity and a 10 mg vial at 95% purity hold the same mass but a different fraction of the target peptide. Lyophilized peptides also carry counter-ions and residual water, so some certificates report a separate net peptide content figure; read whichever your laboratory's calculations require. Terms are defined in the glossary.
How to read the label
- Product name and, where relevant, the sequence or variant.
- Net content in milligrams.
- Lot or batch number, the key to the certificate of analysis.
- Research use only statement.
How to read the certificate
Find the lot number first and confirm it matches the vial. Then read HPLC purity, the mass spectrometry result against the theoretical mass, appearance and test date. If the certificate lacks a lot number or a test date, ask the supplier for the correct document before the vial enters inventory. A certificate that cannot be tied to a lot is not evidence for the vial on your bench.
Storing sealed vials
Keep sealed lyophilized vials cold, dark and dry; long-term storage is typically frozen. Bring a vial to room temperature before opening so moisture does not condense on the powder. Log the lot number and receipt date. What happens after the seal is broken is governed by the laboratory's own written procedures.
Where to go next
Catalog by vial size: /shop. Definitions: /glossary. For the certificate side in more depth, see research peptides with third-party COA; all guides are at research peptides for laboratories.
For Research Use Only. This product is intended for laboratory and scientific research purposes only. It is not a drug or dietary supplement and is not for human or veterinary consumption. Not intended to diagnose, treat, cure, or prevent any disease. The statements made on this website have not been evaluated by the US Food and Drug Administration.
