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How to Reconstitute Peptides

A complete guide to safely mixing lyophilized peptides with bacteriostatic water. Follow these steps for accurate and safe reconstitution every time.

What You Need

Lyophilized peptide vial

The sealed vial containing your freeze-dried peptide powder

Bacteriostatic water (BAC water)

Sterile water with 0.9% benzyl alcohol preservative

Insulin syringes (U-100)

For drawing and injecting. 1 mL size recommended for reconstitution

Alcohol swabs

70% isopropyl alcohol pads for sanitizing vial tops

Step-by-Step Reconstitution Process

1

Calculate Your Concentration

Before mixing, decide how much bacteriostatic water to add. Use our calculator to determine the right amount based on your desired dose and syringe precision. A common approach: add enough water so your typical dose falls between 10-50 units on a U-100 syringe for easy measuring.

2

Sanitize Everything

Wash your hands thoroughly with soap. Swab the top of both the peptide vial and the BAC water vial with separate alcohol pads. Let the alcohol dry completely (about 30 seconds) before proceeding. This step prevents bacterial contamination.

3

Draw the Bacteriostatic Water

Using a fresh syringe, pull the plunger back to draw in air equal to the volume of water you plan to withdraw. Insert the needle into the BAC water vial and push the air in (this equalizes pressure). Then invert the vial and slowly draw your desired amount of water.

4

Add Water to the Peptide Vial

Insert the needle through the peptide vial's rubber stopper. Aim the needle tip at the inside wall of the vial, NOT directly at the powder cake. Slowly push the plunger to release the water. Let the water run gently down the glass wall and contact the powder gradually. This gentle approach prevents damaging the peptide.

5

Dissolve the Peptide

Once all the water is added, remove the syringe. Gently swirl the vial in a circular motion or roll it between your palms. NEVER shake the vial. Most peptides dissolve within 30 seconds to 2 minutes. The solution should be clear and colorless. If slight cloudiness remains, set it in the refrigerator for 10 minutes and check again.

6

Label and Store

Write the reconstitution date and concentration on the vial or a label. Store immediately in the refrigerator at 2-8 C (36-46 F). Keep upright and away from light. Most peptides are stable for 14-30 days after reconstitution.

7

Draw Your Dose

When ready to use, swab the vial top with alcohol. Draw air into your syringe equal to your dose volume, insert into the vial, push air in, invert, and slowly draw your dose. Tap out any air bubbles. Use our calculator to determine exactly how many units to draw for your desired dose.

Common Mistakes to Avoid

xSpraying water directly onto the peptide powder (aim at the vial wall instead)
xShaking the vial (swirl gently or roll between palms)
xUsing the same needle for reconstitution and injection (use a fresh needle each time)
xStoring reconstituted peptides at room temperature (always refrigerate)
xForgetting to label the reconstitution date (set reminders to discard after expiry)
xDrawing from the vial without first pushing in an equal volume of air (creates a vacuum)
xUsing tap water or distilled water without preservative (use BAC water only)

Frequently Asked Questions

You can, but sterile water does not contain a preservative. With sterile water, the reconstituted peptide must be used within 24 hours and cannot be reused. Bacteriostatic water (with 0.9% benzyl alcohol) allows multi-dose use for up to 30 days.
Shaking can create foam and potentially damage the peptide molecules through mechanical agitation. Always swirl gently instead. If foam does form, let the vial sit undisturbed in the refrigerator until the foam dissipates.
Most reconstituted peptides remain stable for 14-30 days when stored properly at 2-8 C (36-46 F). The specific stability varies by peptide -- check our peptide database for details on each peptide.
No. Freezing reconstituted peptides can cause the solution to expand, damaging the peptide molecules and potentially cracking the vial. Only lyophilized (dry powder) peptides can be frozen for long-term storage.
Gently roll the vial between your palms for 1-2 minutes. If particles remain, let it sit in the refrigerator for 15-30 minutes and try again. If it still does not dissolve, the peptide may be degraded -- do not use it.
The amount of water determines the concentration but does not affect the peptide itself. More water = lower concentration (larger volume per dose). Less water = higher concentration (smaller volume per dose). Use our calculator to determine the best amount for your dosing needs.

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