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Reconstitution Calculator

Works for both peptides (mg) and growth hormone (IU), in either direction. Know your water and want the draw? It returns the concentration and exactly how many units to pull on a U-100 syringe. Know the dose and the draw size you want? Switch to “Water to add” and it tells you how much bacteriostatic water to reconstitute with.

mg
mL

Assumes a U-100 insulin syringe (100 units = 1 mL). For laboratory research calculations only, not medical or human-dosing advice.

Result
Draw on a U-100 syringe
5 units
= 0.05 mL
0255075100
Concentration
5 mg/mL
5,000 mcg/mL
Draws per vial
≈ 40 draws

How to reconstitute a peptide

Reconstitution is the process of dissolving a lyophilized (freeze-dried) peptide back into liquid with bacteriostatic water. Work clean and gentle. The steps below are the standard handling routine.

01
Bring vials to room temperature

Let the lyophilized peptide vial and your bacteriostatic water sit out until they reach room temperature. This reduces condensation and clumping.

02
Sanitize both stoppers

Wipe the rubber stopper on the peptide vial and the bacteriostatic water vial with a fresh alcohol swab. Let them air-dry.

03
Draw your bacteriostatic water

Use the calculator above to pick a water volume. More water = lower concentration = more units per draw (easier to measure small amounts). Draw that volume of bacteriostatic water into a syringe.

04
Add water slowly down the vial wall

Insert the needle and let the water run slowly down the inside wall of the peptide vial. Never spray it directly onto the powder. Aggressive streams can denature the peptide.

05
Swirl, don't shake

Gently swirl or roll the vial until the powder fully dissolves into a clear solution. Shaking creates foam and can damage the peptide. If it won't dissolve, let it sit a few minutes and swirl again.

06
Label and refrigerate

Write the date and the diluent volume on the vial so the concentration is reproducible. Store reconstituted peptide at 2–8 °C (refrigerated) and protect it from light. Use within ~2–4 weeks.

For laboratory research use only. Not for human or animal consumption. The calculator and this guide describe handling procedure, not medical or dosing advice. Must be 21+.

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