Peptide reconstitution calculator
Reconstitution is the step where a lyophilized research peptide is dissolved into liquid so a precise amount can be measured. Enter the milligrams in your vial and the volume of bacteriostatic water you plan to add; this tool returns the resulting concentration and the volume that holds a given amount, in millilitres and insulin-syringe units. For in-vitro research planning only.
Research planning arithmetic only. Not medical, dosing, or usage guidance. RTT products are laboratory research reagents for in-vitro use, not for human or animal consumption.
How reconstitution works
A freeze-dried peptide is a dry cake or powder that cannot be measured by volume on its own. Reconstitution dissolves it into a known volume of diluent, giving a solution at a defined concentration. From that point, the amount held in any given volume is fixed by simple arithmetic.
Why the water volume changes everything
The same vial can be set to almost any concentration depending on how much water you add. A 10 mg vial reconstituted with 2 mL of bacteriostatic water holds 5 mg/mL, or 5000 mcg/mL. Drawing 0.1 mL, which is 10 units on a U-100 syringe, takes up 500 mcg. Halve the water to 1 mL and those same 10 units now hold 1000 mcg. Nothing about the peptide changed, only the dilution.
Bacteriostatic versus sterile water
Bacteriostatic water carries about 0.9% benzyl alcohol, a preservative that lets a sealed multi-use vial be drawn from over roughly 28 days. Sterile water has no preservative and suits single use. Both are stocked in reconstitution supplies.
Storage after reconstitution
Lyophilized peptide is generally held frozen near minus 20 C. Once in solution, vials are usually refrigerated at 2 to 8 C and used within the compound's stability window. The storage detail for each lot appears on its product page and certificate of analysis.
Reconstitution questions
What is peptide reconstitution?
Reconstitution is dissolving a lyophilized (freeze-dried) research peptide back into liquid using a sterile diluent, usually bacteriostatic water. Dry peptide cannot be measured by volume on its own; once it is in solution at a known concentration, a precise amount can be drawn for laboratory work.
How much bacteriostatic water should I add?
There is no single correct volume. More water gives a lower concentration and a larger, easier-to-read draw; less water gives a higher concentration and a smaller draw. Many researchers pick a volume that makes the target amount land on a round number of syringe units. Enter different volumes above to compare.
What is the difference between bacteriostatic and sterile water?
Bacteriostatic water contains about 0.9% benzyl alcohol, a preservative that inhibits bacterial growth and lets a sealed multi-use vial be drawn from repeatedly over roughly 28 days. Sterile water carries no preservative and is intended for single use.
How do insulin-syringe units relate to millilitres?
On a U-100 insulin syringe, 100 units equal 1 mL. So 50 units is 0.5 mL and 10 units is 0.1 mL. The calculator converts the draw volume into units automatically.
How should a reconstituted vial be stored?
Lyophilized peptide is generally kept frozen near minus 20 C before reconstitution. Once in solution, vials are usually refrigerated at 2 to 8 C and used within the stability window for that compound. Each product page and its certificate list the storage detail for that lot.
How is concentration calculated?
Concentration is the peptide mass divided by the diluent volume. A 5 mg vial dissolved in 1 mL of water is 5 mg/mL, the same as 5000 mcg/mL. That is exactly the arithmetic this tool runs.