Lyophilization is a drying process.

Lyophilization, often called freeze-drying, removes water from a frozen material under reduced pressure. The resulting material may appear as a compact cake, film, or loose powder depending on formulation and processing conditions.

Mass is not concentration.

A vial label may state the mass of material in milligrams or micrograms. Concentration is a separate value that depends on both the mass and the final liquid volume used in a laboratory protocol.

Record the variables.

For reproducible laboratory calculations, document the labeled or tested mass, diluent volume, desired measurement, and syringe or pipette scale in the laboratory record.