Many research peptides arrive as a lyophilized powder that must be dissolved — or “reconstituted” — into a liquid before it can be used in the laboratory. Doing this carefully protects the compound and keeps measurements accurate. The following is general laboratory background for research handling only.

Choosing a solvent

A common choice for reconstitution in a research setting is sterile or bacteriostatic water, which dissolves many peptides and limits microbial growth. Some peptides that are poorly water-soluble may require a small amount of a co-solvent; the product documentation or supplier is the best guide for a specific sequence.

Working cleanly

Reconstitution should be done with clean technique to avoid introducing contaminants. Add the solvent slowly down the inside wall of the vial rather than directly onto the powder, and let the peptide dissolve gently — swirling rather than vigorous shaking, which can stress the molecule and cause foaming.

Concentration and record-keeping

The concentration of a solution is simply the mass of peptide divided by the volume of solvent added. Recording the exact mass, solvent and volume for each vial lets you calculate concentration precisely and reproduce the preparation later. Labels with the date of reconstitution are invaluable when tracking how long a solution has been in use.

After reconstitution

• Keep the solution refrigerated and use it within a limited period.
• Prepare only what you need; leave the remainder lyophilized and frozen.
• Note the concentration and date on the vial.

This article describes general laboratory handling for research use only. All products are intended strictly for scientific research and are not for human or animal use.