How to Reconstitute Peptides
Step-by-Step Guide for Laboratory Research
Most peptides arrive as a white, lyophilized (freeze-dried) powder in a sealed vial. To use them in research, they must be reconstituted - dissolved in a sterile liquid such as Bacteriostatic Water (BAC Water). This guide walks you through the process step by step.
- Lyophilized peptide vial
- Bacteriostatic Water (BAC Water)
- Alcohol swabs
- Insulin syringe (1 mL, 100 units)
- Sterile mixing syringe (3 mL or 5 mL)
Clean the vial stoppers
Wipe both the peptide vial and the BAC water vial tops with an alcohol swab.
Draw the BAC water
Using a sterile syringe, pull up the desired amount of BAC water (see below for how much).
Inject slowly
Insert the needle into the peptide vial and let the water flow slowly down the inside wall — avoid spraying directly onto the powder.
Swirl gently
Do not shake. Roll or swirl the vial until the powder fully dissolves. The solution should be clear, without flakes or cloudiness.
Label the vial
Write the concentration (e.g., "5 mg/mL"), the date mixed, and storage instructions.
Store correctly
Keep reconstituted peptides refrigerated (2–8 °C). Most remain stable for 20–30 days.
This depends on how concentrated you want your solution to be. A common starting point is 2 mL of BAC water into a 10 mg vial, which makes a concentration of 5 mg/mL. On a 100-unit insulin syringe, that equals 1 mg for every 20 units.
Instead of doing math by hand, use our Peptide Dose Calculator to instantly generate reconstitution ratios for any vial size and desired concentration.
Example - 10 mg Peptide Vial
| BAC Water Added | Final Concentration | Insulin Syringe Reading |
|---|---|---|
| 1 mL | 10 mg/mL | 1 mg = 10 units |
| 2 mL | 5 mg/mL | 1 mg = 20 units |
| 4 mL | 2.5 mg/mL | 1 mg = 40 units |
- Always use BAC water instead of plain sterile water if you plan to store the peptide for more than one use.
- If the solution looks cloudy or has particles that won't dissolve, discard it - this may indicate contamination or poor peptide quality.
- Write everything on the label (name, concentration, date) so there's no confusion later.
For Laboratory Research Only
This guide is for informational purposes related to laboratory research protocols. Not for human or veterinary use. All procedures should be performed by qualified laboratory personnel in appropriate research settings.
