RECONSTITUTION
Contents
How Researchers Reconstitute Lyophilized Peptides: Best Practices for Lab Use (2025 Guide)
Disclaimer: This information is provided strictly for laboratory research purposes. Not for human or veterinary use. Peptides are for Research Use Only (RUO).
What Does It Mean to Reconstitute a Peptide?
- Peptide compounds are typically shipped as lyophilized (freeze-dried) powders to ensure stability and shelf life. Before they can be used in lab experiments, these compounds must be reconstituted — that is, dissolved in a sterile liquid (solvent) under laboratory conditions.
- Important: Reconstitution protocols vary depending on the compound and experiment design. Always follow your institution’s lab safety guidelines.
Common Solvents Used in Laboratory Reconstitution
- Researchers typically reconstitute peptides using one of the following sterile solvents:
Solvent
Description
Use Case
Bacteriostatic Water (BAC Water)
Sterile water with 0.9% benzyl alcohol (antimicrobial preservative)
Often used in labs for multi-use vials
Sterile Water (SWFI)
Water for injection with no preservatives
Ideal for single-use, short-term experiments
0.6% Acetic Acid
Weak acid solution used to increase solubility
Suitable for peptides that resist neutral pH solvents
DMSO
Organic solvent with excellent compound penetration
Use only with proper ventilation and lab protection
Note: Solvent selection should be based on the peptide’s solubility profile and experimental needs.
Step-by-Step: Peptide Reconstitution in the Lab
1. Prepare a Clean Work Area
- Use a laminar flow hood or sanitized bench space
- Wear gloves, eye protection, and follow lab safety protocols
2. Determine the Desired Concentration
- Decide how concentrated you want your solution to be (in mg/mL)
- Use the formula:
Concentration (mg/mL) = Total Peptide (mg) ÷ Volume of BAC Water (mL) - Example: To create a 2.5 mg/mL solution with a 5 mg vial, add 2 mL of bacteriostatic water.
⚠ Be precise: Use a calculator to ensure dosing consistency across your study.
3. Prepare the Vial for Reconstitution
- Wipe the rubber stopper of the peptide vial with a 70% isopropyl alcohol prep pad
- Draw your calculated amount of bacteriostatic (BAC) water using a sterile syringe
- Insert the needle into the vial at a 45°–90° angle to reduce rubber coring
- Inject the BAC water slowly, aiming it against the inside wall of the vial — not directly onto the powder
4. Mix Gently to Dissolve
- Gently swirl the vial in a circular motion (do not shake)
- Avoid creating bubbles or foam — this can damage fragile peptides
- Let it sit for a few minutes if needed until the peptide is fully dissolved
Storage Tips (Lab-Use Only)
- Store reconstituted peptides at 2–8°C (refrigerated)
- Label vials clearly with:
- Compound name
- Concentration (e.g., 2.5 mg/mL)
- Date of reconstitution
Do not refreeze after reconstitution (unless approved by lab protocol)- For long-term storage, keep lyophilized peptides in a frost-free -20°C freezer in their original sealed vials
Disposal & Safety Notes
- Discard unused solution after 14–30 days, depending on compound stability
- Follow all lab biohazard disposal rules for solvents and vials
- Maintain a log of reconstitution dates and batch numbers for research traceability