RECONSTITUTION GUIDE
How Much BAC Water for P21?
Quick answer: Add 2 mL of bacteriostatic water to a 10 mg P21 vial. This yields a concentration of 5000 µg/mL. A standard 500 µg research dose then requires 0.1 mL (10 IU on a 100-unit insulin syringe).
Concentration by BAC water volume
Concentration and 500 µg draw volume at common BAC water volumes for a 10 mg vial.
| BAC water | Concentration | Dose volume | Draw |
|---|---|---|---|
| 1 mL | 10000 µg/mL | 0.05 mL | 5 IU |
| 2 mL Standard | 5000 µg/mL | 0.1 mL | 10 IU |
| 3 mL | 3333.33 µg/mL | 0.15 mL | 15 IU |
| 5 mL | 2000 µg/mL | 0.25 mL | 25 IU |
Dose volume at the standard 5000 µg/mL concentration
How draw volume changes if you vary the dose at the standard 10 mg + 2 mL reconstitution.
| Dose | Volume | IU draw (100u) |
|---|---|---|
| 250 µg | 0.05 mL | 5 IU |
| 500 µg Std | 0.1 mL | 10 IU |
| 750 µg | 0.15 mL | 15 IU |
| 1000 µg | 0.2 mL | 20 IU |
| 1500 µg | 0.3 mL | 30 IU |
Reconstitution steps
- Wipe the top of both the P21 vial and the bacteriostatic water vial with alcohol swabs.
- Draw 2 mL of bacteriostatic water into a sterile syringe.
- Inject the water slowly down the inside glass wall of the P21 vial. Do not aim directly at the powder.
- Swirl gently until fully dissolved. Never shake.
- Refrigerate at 2–8°C protected from light. Allow to reach room temperature before each draw.
Supplies needed
- P21 10 mg lyophilized vial
- 2 mL bacteriostatic water (0.9% benzyl alcohol)
- 100-unit (1 mL) U-100 insulin syringe
- Alcohol swabs
- Sharps container for disposal
Frequently asked
How much BAC water do I add to a 10 mg P21 vial?
For the standard ASCEND research protocol, add 2 mL of bacteriostatic water to a 10 mg P21 vial. This yields 5000 µg/mL.
What concentration does 2 mL BAC water give for 10 mg P21?
A 10 mg P21 vial reconstituted with 2 mL of bacteriostatic water yields 5000 µg/mL. A 500 µg dose then requires 0.1 mL (10 IU on a 100-unit insulin syringe).
Can I use sterile water instead of bacteriostatic water for P21?
Bacteriostatic water (0.9% benzyl alcohol) is preferred because it inhibits bacterial growth and allows multi-dose use of the reconstituted vial. Sterile water lacks preservative properties and accelerates peptide degradation once the vial is opened.
How long is P21 stable once reconstituted with BAC water?
Most research peptides remain stable for approximately 28 days when reconstituted with bacteriostatic water and stored at 2–8°C protected from light. Refer to peptide-specific stability data for any deviation from this baseline.
What size insulin syringe should I use for P21?
For a 500 µg dose (10 IU draw), a 30-unit (0.3 mL) U-100 insulin syringe gives the finest resolution. A 100-unit syringe also works.
Related
For research use only. Not medical advice. Consult a qualified healthcare provider before using any peptide compound. Reconstitution parameters cross-referenced with independent 3rd-party analytical laboratories. · ASCEND · ascendpeptide.org