Peptide Reconstitution Calculator & Mixing Guide
Work out the exact concentration of a reconstituted research vial, convert milligrams to micrograms, and translate the draw volume into U-100 syringe units. For in-vitro laboratory research use only.
Reconstitution calculator
- Concentration
- 5 mg/mL
- 5,000 mcg/mL
- Draw volume
- 0.05 mL
- U-100 syringe units
- 5
Formula: concentration = vial mass ÷ diluent volume. Draw volume = aliquot ÷ concentration. 100 units on a U-100 syringe equal 1 mL.
How to reconstitute a research peptide, step by step
1. Equilibrate the vial
Let the lyophilized vial reach room temperature before opening so condensation does not form on the powder.
2. Sanitize both stoppers
Wipe the peptide vial stopper and the bacteriostatic water stopper with an alcohol prep pad and allow them to dry.
3. Draw the diluent
Withdraw the calculated volume of bacteriostatic water into a sterile syringe.
4. Add slowly down the wall
Angle the needle so the diluent runs down the inside wall of the vial rather than striking the powder directly.
5. Dissolve without shaking
Swirl gently or let the vial stand until the solution is clear. Never shake — agitation shears peptide bonds.
6. Label and refrigerate
Record the concentration and reconstitution date on the vial, then store at 2–8 °C away from light.
Peptide mixing chart
| Vial size | Bacteriostatic water | Concentration | Per 10 units (0.1 mL) |
|---|---|---|---|
| 2 mg | 1 mL | 2 mg/mL | 200 mcg |
| 5 mg | 1 mL | 5 mg/mL | 500 mcg |
| 5 mg | 2 mL | 2.5 mg/mL | 250 mcg |
| 10 mg | 1 mL | 10 mg/mL | 1,000 mcg |
| 10 mg | 2 mL | 5 mg/mL | 500 mcg |
| 10 mg | 3 mL | 3.33 mg/mL | 333 mcg |
| 15 mg | 3 mL | 5 mg/mL | 500 mcg |
| 20 mg | 2 mL | 10 mg/mL | 1,000 mcg |
| 30 mg | 3 mL | 10 mg/mL | 1,000 mcg |
| 50 mg | 5 mL | 10 mg/mL | 1,000 mcg |
Storage & shelf life
Before mixing: keep the vial dry and sealed
Follow the storage conditions and expiry or retest date supplied for the specific compound and lot. Lyophilized material and prepared solutions do not have the same storage requirements. Protect the unopened vial from moisture and light, and let it reach room temperature while still sealed before opening to reduce condensation.
After mixing: how long does it last in the fridge?
There is no single fridge-life figure that applies to every research peptide. Stability depends on the compound, solvent, concentration, container and handling. Refrigeration at 2–8 °C is appropriate only where the compound’s documentation or validated laboratory protocol specifies it; refrigeration alone does not establish an expiry date. Use a documented working window rather than assuming a universal 28-day or 30-day shelf life.
Label each prepared vial with its compound, lot, solvent, concentration and preparation date. Protect it from light and avoid repeated freeze–thaw cycles. If a validated protocol calls for freezing, prepare suitable single-use aliquots. A clear-looking solution is not proof of chemical stability or freedom from contamination.
Bacteriostatic water is not a shelf-life guarantee
Follow the water manufacturer’s label for storage and handling after opening. A preservative can limit microbial growth, but it does not prevent peptide degradation or establish how long a mixed peptide remains suitable for a laboratory experiment. The water’s expiry date is not the prepared peptide’s expiry date.
For more detail, read our peptide storage: temperature and light and sterile water vs. bacteriostatic water references.
Bac water for a 10mg Retatrutide vial
There is no universal volume of bacteriostatic water to add to a 10mg Retatrutide vial. The required laboratory concentration determines the volume, provided the diluent is compatible with the compound and the volume fits the vial. Check the material’s documentation and your laboratory protocol first.
As a concentration example only, 10 mg in a final solution volume of 2 mL gives 5 mg/mL; a final volume of 1 mL gives 10 mg/mL. These figures use the labelled mass, not an independently measured peptide content. They are not recommended mixing volumes, dosing instructions or evidence of a storage window.
Review the available strengths and lot documentation on the Retatrutide product page and find bacteriostatic water supplies in our product catalog. The reconstitution supply listing includes water options and is sold through the catalog rather than a separate product page.
Reconstitution FAQ
What is peptide reconstitution?
Reconstitution is the laboratory process of dissolving a lyophilized (freeze-dried) peptide powder in a sterile diluent — most commonly bacteriostatic water — so the material can be measured accurately in solution for in-vitro research work.
How do you calculate research peptide concentration?
Concentration equals the vial's peptide mass divided by the volume of diluent added. A 10 mg vial reconstituted with 2 mL of bacteriostatic water yields 5 mg/mL, or 5,000 mcg per mL.
How many units on a U-100 syringe equal a given volume?
A standard U-100 syringe is graduated so that 100 units equal 1 mL. Multiply the volume in mL by 100 to convert to syringe units — 0.25 mL is 25 units.
Which diluent should be used?
Bacteriostatic water is standard for multi-draw laboratory storage because the benzyl alcohol content limits microbial growth. Some poorly water-soluble compounds, such as SLU-PP-332, are prepared with a half DMSO and half bacteriostatic water mixture.
How should reconstituted research peptides be stored?
Keep reconstituted vials refrigerated at 2–8 °C, protected from light, and avoid repeated freeze-thaw cycles. Lyophilized powder is far more stable and should stay frozen until the day of reconstitution.
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All products and calculations on this page are intended strictly for in-vitro laboratory research only and are not intended for diagnosis or treatment.