Understanding reconstitution
Reconstitution is the process of adding a solvent to a lyophilised (freeze-dried) peptide to create a solution at a specific concentration. Done correctly, it takes under a minute and preserves the full integrity of the compound. Done incorrectly, it can compromise your research before it begins.
Step-by-step protocol
Calculate your target concentration
Before opening anything, determine how much solvent you need. Divide the peptide mass (in mg) by your desired concentration (in mg/mL) to get the solvent volume. Our reconstitution calculator does this for you automatically.
Prepare your workspace
Work on a clean, flat surface. Have your solvent (bacteriostatic water or sterile water), an appropriately sized syringe, alcohol swabs, and the peptide vial ready. Allow the lyophilised vial to reach room temperature before reconstituting — approximately 10 minutes after removing from the refrigerator.
Swab the vial septum
Clean the rubber stopper on both the peptide vial and the solvent vial with an alcohol swab. Allow to air dry for a few seconds. This prevents introducing contaminants.
Draw the solvent
Using a sterile syringe, draw the calculated volume of bacteriostatic water (or sterile water). Remove any air bubbles by tapping the syringe gently and pushing them out.
Add solvent to the peptide vial
Insert the needle through the septum and direct the solvent stream against the glass wall of the vial — not directly onto the powder. Let the liquid trickle down and contact the lyophilised cake gently. This is critical: direct force can denature the peptide.
Allow to dissolve
Most lyophilised peptides will dissolve within 30-60 seconds. If any powder remains, tilt the vial gently or roll it slowly between your palms. Never shake or vortex. The solution should be clear — if it appears cloudy or contains particles, do not use it.
Refrigerate immediately
Once reconstituted, store the vial upright at 2-8°C. Label the vial with the date, compound name, and concentration. Use within 30 days (bacteriostatic water) or 7-14 days (sterile water).
Bacteriostatic water vs sterile water
Bacteriostatic water
Contains 0.9% benzyl alcohol as preservative
Inhibits microbial growth — allows multi-use
Reconstituted solution viable for up to 30 days
Recommended for most research peptides
Sterile water
No preservatives — pure H₂O
No antimicrobial protection — single-use ideal
Use within 7-14 days after reconstitution
Required when benzyl alcohol sensitivity is a concern
Calculating dilution volumes
The formula is straightforward: Volume (mL) = Peptide mass (mg) ÷ Desired concentration (mg/mL). For example, a 10mg vial reconstituted with 2mL of bacteriostatic water gives a concentration of 5mg/mL (or 5,000mcg/mL).
Our reconstitution calculator handles unit conversions, syringe markings, and common concentration targets automatically.
Open reconstitution calculatorCommon errors that compromise integrity
Error
Injecting solvent directly onto the powder
Correct approach
Direct the stream against the vial wall and let it trickle down. This prevents denaturing the peptide with hydraulic force.
Error
Shaking or vortexing the vial
Correct approach
Gentle swirling only. Vigorous agitation creates foam and introduces air that can oxidise the compound.
Error
Using the wrong solvent volume
Correct approach
Always calculate your target concentration before reconstituting. Use our calculator to verify volumes.
Error
Storing reconstituted peptides at room temperature
Correct approach
Reconstituted peptides must be refrigerated at 2-8°C immediately. Room temperature accelerates degradation.
Error
Reusing needles or contaminating the septum
Correct approach
Use a fresh sterile needle for each draw. Swab the vial septum with alcohol before every puncture.
Storage after reconstitution
Refrigerate at 2-8°C
Store reconstituted vials upright in the refrigerator. Avoid the door shelf where temperature fluctuates. The back of the main compartment provides the most consistent temperature.
Avoid freeze-thaw cycles
Do not freeze reconstituted peptide solutions. Repeated freezing and thawing damages the peptide structure through ice crystal formation and concentration shifts. Refrigeration only.
Related resources
For research and laboratory purposes only. Not for human use. These statements have not been evaluated by the Therapeutic Goods Administration (TGA). This product is not intended to diagnose, treat, cure, or prevent any disease. Always consult a qualified healthcare professional before starting any new protocol.