What is Reconstitution? (Peptide Glossary)

Reconstitution is the step that converts a freeze-dried peptide cake back into a usable liquid solution. The researcher adds a measured volume of solvent to the vial, allowing the powder to dissolve gently. The choice of solvent matters: bacteriostatic water is the standard for most peptides because its benzyl alcohol content inhibits bacterial growth over multiple withdrawals, while acetic acid solution (0.6%) is used for peptides with solubility or stability issues in plain water.

Technique affects peptide integrity. Best practice is to aim the solvent stream at the vial wall rather than directly onto the peptide cake, and to swirl gently or let it dissolve passively rather than shaking - aggressive agitation can shear or denature fragile peptide chains. Larger peptides and proteins (like IGF-1 LR3) are especially sensitive to rough handling.

Once reconstituted, the clock starts. Most reconstituted peptides should be refrigerated at 2-8C and used within 20-30 days, though stability varies by compound. This is why experienced researchers reconstitute only what a study protocol requires and why vendors who ship pre-reconstituted liquid peptides at ambient temperature should be avoided.