A complete step-by-step guide to safely mixing lyophilized peptides with bacteriostatic water. Covers supplies, technique, storage, and common mistakes.
Wipe the rubber stopper of both the peptide vial and bacteriostatic water vial with an alcohol swab. Allow to air dry for 15-30 seconds. This prevents introducing bacteria into either vial.
Insert the syringe needle through the rubber stopper of the bacteriostatic water vial. Invert the vial upside down and slowly draw your desired amount of water. Common amounts are 1mL or 2mL. Remove any air bubbles by tapping the syringe and pushing them out.
Insert the needle through the rubber stopper of the peptide vial at a slight angle. Slowly release the water down the inside glass wall of the vial. Let gravity do the work — the water should trickle down gently. Never spray water directly onto the lyophilized powder.
Once all water is added, gently swirl the vial in a circular motion. Do not shake, flick, or invert aggressively. The powder should dissolve within 30-60 seconds. The resulting solution should be perfectly clear and colorless.
Write the reconstitution date, peptide name, and concentration on the vial with a marker. Store in the refrigerator at 2-8°C (36-46°F). Most reconstituted peptides last 14-28 days refrigerated.
When ready to use, clean the vial top with an alcohol swab. Insert the syringe and draw air equal to your dose volume. Push the air into the vial (this equalizes pressure), then invert and draw your calculated dose. Use our peptide calculator to determine exact units.
The concentration of your reconstituted peptide depends on two factors: the amount of peptide in the vial (mg) and the amount of water you add (mL).
Concentration (mcg/mL) = Peptide amount (mg) × 1,000 ÷ Water volume (mL)
For example: 5mg peptide + 2mL water = 2,500 mcg/mL
| Vial Size | Water Added | Concentration | mcg per Unit (100u syringe) |
|---|---|---|---|
| 2 mg | 1 mL | 2,000 mcg/mL | 20 mcg |
| 2 mg | 2 mL | 1,000 mcg/mL | 10 mcg |
| 5 mg | 1 mL | 5,000 mcg/mL | 50 mcg |
| 5 mg | 2 mL | 2,500 mcg/mL | 25 mcg |
| 5 mg | 3 mL | 1,667 mcg/mL | 16.7 mcg |
| 10 mg | 1 mL | 10,000 mcg/mL | 100 mcg |
| 10 mg | 2 mL | 5,000 mcg/mL | 50 mcg |
| Syringe Size | Total Units | Best For | Smallest Increment |
|---|---|---|---|
| 0.3 mL | 30 units | Very small doses (under 100 mcg) | 0.5 unit |
| 0.5 mL | 50 units | Small to medium doses (100-500 mcg) | 1 unit |
| 1.0 mL | 100 units | Medium to large doses (500+ mcg) | 1 unit |
Direct water impact can damage peptide molecules through shear force. The powder is delicate — treat it gently.
Shaking creates foam and can denature (break down) the peptide chains. If it doesn't dissolve immediately, let it sit for 5 minutes then swirl again.
Without the benzyl alcohol preservative, bacteria can grow in the solution within hours. Bacteriostatic water keeps the solution safe for weeks.
Heat accelerates peptide degradation. Room temperature storage can reduce potency by 50% or more within days.
Freezing causes ice crystals to form, which can fragment peptide molecules and create aggregates.
Reused needles are dull (increasing pain and tissue damage) and can introduce bacteria. Insulin syringes are inexpensive — always use a new one.
| State | Temperature | Duration | Notes |
|---|---|---|---|
| Lyophilized (powder) | Room temp or below | Months to years | Keep dry, away from light |
| Lyophilized (frozen) | -20°C | Years | Best for long-term storage |
| Reconstituted | 2-8°C (fridge) | 14-28 days | Label with date and concentration |
| Reconstituted | Room temperature | Not recommended | Rapid degradation and contamination risk |