Mannitol
Definition
A sugar alcohol commonly used as a bulking agent and cryoprotectant in lyophilized peptide formulations. It forms the visible powder cake in the vial and helps protect the peptide during the freeze-drying process.
Related Terms in Preparation
Bacteriostatic Water
Sterile water containing 0.9% benzyl alcohol as a preservative. Used to reconstitute lyophilized peptides. Unlike sterile water, it inhibits bacterial growth and allows multi-dose use.
Sterile Water
Water that has been sterilized and contains no preservatives. Unlike bacteriostatic water, it does not inhibit bacterial growth and should be used for single-dose preparations only.
Reconstitution
The process of adding a solvent (usually bacteriostatic water) to a lyophilized peptide to create a liquid solution for use.
Lyophilization
The freeze-drying process used to convert peptide solutions into stable powders for long-term storage. Removes water under vacuum at low temperature, preserving the peptide's molecular structure. Lyophilized peptides can remain stable for years at -20°C.
Lyophilized
Freeze-dried. Peptides are commonly sold in lyophilized (powdered) form to preserve stability during storage. Must be reconstituted before use.
Vial
A small glass or plastic container used to store lyophilized or reconstituted peptides. Typically sealed with a rubber stopper and aluminum crimp cap.
Aliquot
A measured portion of a solution divided from a larger volume. Peptides may be aliquoted into single-use portions to avoid repeated freeze-thaw cycles.
Diluent
A liquid used to dilute or reconstitute a substance. For peptides, common diluents include bacteriostatic water and sterile saline.