Use this calculator to work out the concentration of a reconstituted lyophilised peptide vial, and the volume that contains a given amount of peptide. It is a unit-conversion tool for laboratory measurement only. It does not suggest any amount, and Biolabs research peptides are not for human or veterinary use.
Lab maths tool
Enter the peptide in the vial, the diluent you add and the amount you want to measure. Results update as you type.
- Concentration
- 5 mg/ml
- Per 0.1 ml (10 units)
- 500 mcg
- Volume to measure
- 0.125 ml
- Measures in the vial
- 40
For laboratory research use only. This tool converts units; it does not recommend or suggest any amount. Biolabs research peptides are not for human or veterinary use.
How the calculation works
- Concentration (mg/ml) = peptide in the vial (mg) ÷ diluent added (ml).
- Concentration (mcg/ml) = mg/ml × 1,000.
- Volume for a given amount (ml) = amount wanted (mcg) ÷ concentration (mcg/ml).
- Units on a U-100 scale = volume (ml) × 100. On a U-100 scale, 1 unit is 0.01 ml.
Worked example: a 10 mg vial with 2 ml of diluent gives 5 mg/ml, which is 5,000 mcg/ml. A measurement of 250 mcg is then 0.05 ml, or 5 units on a U-100 scale.
Reconstitution in the lab: the basics
Let the vial reach room temperature, wipe the stopper, then add the diluent slowly down the inside wall of the vial and swirl gently rather than shaking. Most laboratories use bacteriostatic water 10ml (0.9% benzyl alcohol) for multi-use vials or sterile water for single use. Some peptides need 0.6% acetic acid; check the product page. Store reconstituted solution at 2–8 °C and follow your own validated stability protocol. Read more in our guides to bacteriostatic water and lyophilised peptides.
Frequently asked questions
What is the difference between mg and mcg?
1 milligram (mg) is 1,000 micrograms (mcg). Vials are labelled in mg, while research protocols often state amounts in mcg.
Does adding more diluent change the amount of peptide?
No. It changes the concentration. The total peptide in the vial stays the same, so a larger volume of diluent means each 0.1 ml contains less peptide.
What does "units" mean on a syringe?
Insulin-style syringes are marked in units. On a U-100 syringe, 100 units equal 1 ml, so 1 unit is 0.01 ml.
Where can I get reconstitution supplies in South Africa?
See our reconstitution supplies collection for bacteriostatic water, sterile water, acetic acid, PBS and kits. Delivery is free on South African orders over R2,500.
For laboratory research use only. This tool converts units and does not recommend any amount. Biolabs research peptides are not for human or veterinary use and are not intended to diagnose, treat, cure or prevent any disease.