Reconstitution Calculator
Calculate exactly how much bacteriostatic water to add to your peptide vial for a precise concentration. Enter your vial size and desired concentration below.
Add the following amount of bacteriostatic water:
20.00 mL
mL = (vial_mg × 1000) ÷ desired_mcg_per_mL = (5 × 1000) ÷ 250 = 20.00
Step-by-Step Reconstitution Guide
- 1
Clean vial top with alcohol swab and allow to dry.
- 2
Draw 20.00 mL of bacteriostatic water into a sterile syringe.
- 3
Insert needle and slowly inject the water along the side of the vial.
- 4
Gently swirl the vial — never shake.
- 5
Allow to fully dissolve (may take a few minutes). Solution should be clear.
- 6
Store reconstituted peptide at 2–8°C (refrigerator).
Common Reconstitution Reference
| Peptide | Vial Size | Typical Concentration | Water to Add |
|---|---|---|---|
| BPC-157 | 5 mg | 250 mcg/mL | 20.00 mL |
| TB-500 | 5 mg | 500 mcg/mL | 10.00 mL |
| CJC-1295 (no DAC) | 2 mg | 100 mcg/mL | 20.00 mL |
| Ipamorelin | 5 mg | 200 mcg/mL | 25.00 mL |
| GHK-Cu | 10 mg | 500 mcg/mL | 20.00 mL |
What Is Peptide Reconstitution?
Reconstitution is the process of adding a solvent — typically bacteriostatic water (sterile water preserved with 0.9% benzyl alcohol) — to a lyophilized (freeze-dried) peptide vial to create a solution suitable for research use. Lyophilized peptides are shipped as a dry powder to maximize stability during transit and long-term storage.
The concentration of the reconstituted solution depends on two factors: the total amount of peptide in the vial (measured in milligrams) and the volume of solvent added (measured in milliliters). The formula is straightforward:
mL of water = (vial size in mg × 1000) ÷ desired concentration in mcg/mL
For example, to reconstitute a 5 mg vial to a concentration of 250 mcg/mL, you would add 20 mL of bacteriostatic water: (5 × 1000) ÷ 250 = 20 mL.
Always use bacteriostatic water rather than sterile water for reconstitution if the peptide will be stored for more than a single use session. The benzyl alcohol preservative in bacteriostatic water inhibits bacterial growth, keeping the solution safe for multiple withdrawals over its shelf life (typically 28 days when refrigerated at 2–8°C).
Tips for Best Results
- Always inject the water slowly along the inside wall of the vial — never spray directly onto the powder.
- Gently swirl to dissolve. Vigorous shaking can denature the peptide and reduce potency.
- Use insulin syringes or other sterile, low dead-volume syringes for maximum accuracy.
- Label the vial with the reconstitution date, concentration, and peptide name.
- Store reconstituted peptides in a refrigerator (2–8°C). For long-term storage of unreconstituted peptides, a freezer (−20°C) is recommended.