Reconstituting research peptides with bacteriostatic water

Reconstitution is the step that turns a lyophilised powder into a solution you can work with in the laboratory. It is simple, but small choices — the solvent, the technique, the way the vial is handled — affect how cleanly the material dissolves and how stable the solution stays.

Choosing the solvent

• Bacteriostatic water contains a small amount of benzyl alcohol, which slows microbial growth and makes it a common choice when a solution will be kept for a while. Choose it when you need the solution to hold for longer than a single session.
• Sterile water has no preservative, so it suits work where the added alcohol is unwanted and the solution will be used promptly.
• Buffer or saline may be appropriate for specific materials; follow the guidance for the compound you are working with.

For lyophilised material, start with the solvent the material is intended to be dissolved in rather than improvising.

Technique

1. Let the vial reach room temperature before opening, so condensation does not form on the powder.
2. Swab the stopper. Keep the workspace clean.
3. Add the solvent down the inside wall of the vial rather than directing a stream onto the powder; a gentle stream avoids foaming and mechanical stress.
4. Swirl to dissolve. Do not shake — vigorous agitation can damage peptides.
5. Let the solution stand until fully clear, then record the reconstitution date.

Working concentration

Work in the concentration your experiment calls for, and record the volume you added so the concentration is reproducible later. Write it down at the time, not from memory afterwards.

Storing the solution

Keep the reconstituted solution cold and protected from light, and avoid repeated freeze-thaw cycles. Label the vial with the material, the batch number, the concentration and the date it was made.

A note on scope

Reconstitution here is a laboratory technique for preparing working solutions. Our compounds are supplied for laboratory research use only.

The certificate for the batch you are working with is listed on the lab test results page. For storage before and after, see storing lyophilised research peptides and lyophilised vs reconstituted peptides.