Biomatrix · Laboratory Tool
Peptide Reconstitution Calculator
This free calculator helps researchers accurately reconstitute lyophilised peptide compounds by computing the exact syringe draw volume for any given dose. Reconstitution — the process of dissolving a freeze-dried peptide in bacteriostatic water — requires precise measurements to ensure consistent results across laboratory protocols. Incorrect volumes can introduce significant variability into research data, making a reliable calculator an essential part of any peptide research workflow.
How to Use the Peptide Calculator
Enter your vial size
Input the total mass of your lyophilised peptide in milligrams (mg). Use the preset buttons for the most common vial sizes (5mg, 10mg, etc.) or type a custom value.
Set the BAC water volume
Enter the volume of bacteriostatic water (in mL) you plan to add to the vial. This determines the final concentration of your solution. A common starting point is 2mL per 10mg vial.
Input your desired dose
Enter the research dose you need in either micrograms (mcg) or milligrams (mg). Toggle between units using the mcg/mg selector next to the dose field.
Select your syringe size
Choose the insulin syringe size you are working with — 0.3mL (30u), 0.5mL (50u), or 1.0mL (100u). The visual syringe and unit display will update accordingly.
Read the output
The calculator displays your draw volume in mL and insulin syringe units, the resulting concentration in mg/mL, and the total number of doses available from the vial.
Vial Size (Peptide Amount)
BAC Water (Added to Vial)
Desired Dose
Syringe Size
Concentration
5 mg/mL
Doses per Vial
40
1mL / 100 units
5units
0.05 mL
Want to save your protocol?
Store this calculation, track your research schedule and manage laboratory records in BMX Lab Tracker.
How to use: Enter your vial size and the amount of bacteriostatic water you'll add. Then enter your desired dose to see exactly how much to draw.
Tip: 1 mL = 100 units on an insulin syringe. Draw slowly to ensure accuracy.
Reference Guide
Common Vial Sizes
| Peptide | Typical Size |
|---|---|
| BPC-157 | 5mg, 10mg |
| TB-500 | 5mg, 10mg |
| Semaglutide | 3mg, 5mg |
| Ipamorelin | 5mg, 10mg |
| CJC-1295 | 2mg, 5mg |
| Tirzepatide | 5mg, 10mg, 15mg |
Syringe Types
| Size | Units | Best For |
|---|---|---|
| 0.3mL | 30 units | Small doses, precision |
| 0.5mL | 50 units | Most peptides |
| 1mL | 100 units | Larger doses |
Smaller syringes offer better precision for small doses. Use the smallest syringe that fits your dose.
Reconstitution Tips
- ·Use bacteriostatic water (BAC) — contains 0.9% benzyl alcohol for preservation
- ·Inject water slowly — aim down the vial wall, not directly onto powder
- ·Never shake — gently swirl or roll the vial until dissolved
- ·Store properly — refrigerate at 2-8°C after reconstitution
- ·Use within 28 days — most reconstituted peptides remain stable for about 4 weeks
- ·Keep sterile — always clean vial tops with alcohol before drawing
Reconstitution Guide
Step-by-step mixing guide with visuals
Research Supplies
BAC water, syringes & prep pads
Common Reconstitution Questions
How much bacteriostatic water should I add to my peptide vial?
The amount of BAC water you add determines the concentration of your solution. A common convention is to add 2mL of bacteriostatic water to a 10mg vial, giving a concentration of 5mg/mL (5000mcg/mL). For smaller doses or more precise measurements, you may prefer 1mL (giving 10mg/mL). Use the calculator to find the volume that results in easy-to-draw syringe units for your specific dose.
How should I store a reconstituted peptide?
Once reconstituted with bacteriostatic water, peptides should be stored at 2–8°C in a refrigerator. Keep them away from light and avoid repeated temperature fluctuations. Do not freeze reconstituted solutions, as this can cause aggregation and degrade the compound. Most reconstituted peptides in bacteriostatic water remain stable for approximately 4–8 weeks when refrigerated correctly.
How do I calculate the correct dose in syringe units?
On a standard U-100 insulin syringe, 1 unit = 0.01mL. To calculate units: divide your desired dose (in mg) by the concentration (mg/mL), then multiply by 100. For example, a 250mcg dose from a 5mg/mL solution requires 0.05mL = 5 units. The Biomatrix calculator performs this automatically — simply enter your vial size, water volume, and dose.
What is the difference between mcg and mg when dosing?
1 milligram (mg) equals 1000 micrograms (mcg). Many research peptides are dosed in microgram quantities (e.g. 100mcg, 250mcg, 500mcg), while others — particularly GLP-1 compounds like Semaglutide — are typically referenced in milligrams (e.g. 0.5mg). The calculator accepts both units — use the toggle next to the dose field to switch between mcg and mg.
Why is bacteriostatic water used instead of plain sterile water?
Bacteriostatic water contains 0.9% benzyl alcohol, which inhibits the growth of bacteria and extends the usable life of a reconstituted solution to approximately 4–8 weeks. Plain sterile water has no preservative and reconstituted solutions should be used within 24 hours. For multi-use vials in a laboratory setting, bacteriostatic water is strongly preferred. Biomatrix supplies bacteriostatic water in the Research Supplies category.
Research Purposes Only
These calculators are provided for educational and research purposes only. Always verify calculations and consult with qualified professionals. The information provided is not medical advice. Peptides should only be used in accordance with applicable laws and regulations.