A precise, step-by-step protocol for safely mixing lyophilized peptides with bacteriostatic water — plus a live calculator to work out your concentration in seconds.

5Simple Steps

<5Minutes Needed

2-8°Store (°C)

100%Sterile Technique

The Basics

What Is Reconstitution?

Reconstitution is the process of mixing a lyophilized (freeze-dried) peptide with a diluent — typically bacteriostatic water — to prepare a liquid solution suitable for precise measurement in research settings.

Peptides are shipped as a stable powder to preserve potency during transit and storage. Reconstitution converts that powder into a usable liquid, and the volume of water you add determines the final concentration — which is why getting the ratio right matters.

Below you'll find the general step-by-step process, a live calculator to determine your exact concentration, the supplies you need on hand, and key do's and don'ts to follow.

Lyophilized Peptide

Stable freeze-dried powder, shipped cold-chain and ready to reconstitute.

Bacteriostatic Water

Contains 0.9% benzyl alcohol to inhibit bacterial growth in the solution.

Sterile Syringe

Used to accurately draw and transfer water without contamination.

Refrigeration

Reconstituted solution should be stored cold and used within its window.

The Process

General Steps

Sanitize Everything

Clean your work surface and wash your hands thoroughly. Wipe the rubber tops of both the peptide vial and the bacteriostatic water vial with an alcohol swab and let them air-dry.

Draw the Water

Using a sterile syringe, draw air equal to your intended water volume, inject it into the bacteriostatic water vial, then draw out the required volume of water.

Inject Slowly

Insert the needle into the peptide vial at an angle and inject the water slowly down the inside wall of the glass — never directly onto the powder, which can damage the peptide structure.

Swirl Gently

Gently swirl the vial in small circular motions until the powder is fully dissolved. Do not shake — vigorous agitation can denature the peptide.

Store Correctly

Label the vial with the date and concentration, then refrigerate at 2–8°C. Use within the recommended window (typically 2–4 weeks) for best stability.

This guide is provided for general research reference only. Always follow your lab's specific protocols and safety data sheets.

Interactive Tool

Reconstitution Calculator

Enter your peptide amount and the water volume you plan to add — we'll calculate concentration and units-per-dose instantly.

Peptide Amount (mg)

Bacteriostatic Water (mL)

Desired Dose (mcg)

Concentration

Per Dose (100u syringe)

Total Doses

Best Practices

Do's & Don'ts

Do

Sanitize vial tops with alcohol swabs before every use.
Inject water slowly down the inside wall of the vial.
Swirl gently until fully dissolved.
Label vials with date and concentration.
Store refrigerated at 2–8°C.

Don't

Shake the vial vigorously — this can damage the peptide.
Inject water directly onto the powder.
Use non-sterile water or expired diluent.
Leave reconstituted solution at room temperature.
Use past the recommended stability window.

Common Questions

Reconstitution FAQ

This depends on your desired concentration and dosing preference. Use the calculator above — enter your peptide mg and your target water volume to instantly see the resulting concentration in mcg/mL.

Bacteriostatic water contains 0.9% benzyl alcohol which inhibits bacterial growth, allowing the reconstituted solution to be used over multiple sessions. Sterile (non-bacteriostatic) water lacks this preservative and is intended for single, immediate use only.

Most reconstituted peptides remain stable for 2–4 weeks when stored refrigerated at 2–8°C, away from light. Always check your specific peptide's certificate of analysis and datasheet for exact stability guidance.

Let the vial sit at room temperature for a few minutes and gently swirl again. Avoid shaking. If particulate matter remains after several attempts, do not use the vial — contact us for guidance.

Keep Learning

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