What does lyophilisation mean?
Lyophilisation is a technical process for removing water from a substance by freezing it and then allowing the ice to sublime under reduced pressure. In everyday terms, it is freeze-drying. Because the water is removed without substantially heating the material, lyophilisation is especially useful for preserving heat-sensitive products such as pharmaceuticals, vaccines, biological specimens, and some foods. The resulting material is typically a light, dry powder, and it can often be reconstituted by adding water. The word is most common in British English and specialist scientific writing, while American English usually uses lyophilization. Although dehydration describes the broad removal of water, lyophilisation identifies the more specific method of freezing and sublimation that helps maintain the structure and stability of the original material.
nounThe process of removing water from a substance by freezing it and then sublimating the ice under reduced pressure. It is also known as freeze-drying and is used to preserve foods, biological materials, and other heat-sensitive substances.
- The process of freeze-drying a substance by removing water from it as ice under reduced pressure.
- The process of dehydrating a substance through freezing and sublimation, especially for preserving foods, pharmaceuticals, or biological specimens.
"The pharmaceutical was preserved by lyophilisation, producing a stable powder for injection."
"Lyophilisation produces a dry powder that can be reconstituted with water."
"The samples were stored in their lyophilised form until they were needed for analysis."
The plural is used when referring to multiple freeze-drying processes.
"The laboratory compared lyophilisations of several protein samples."
Lyophilisation turns frozen water straight into vapour, allowing medicines and foods to be preserved without the heat of conventional drying.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of lyophilisation
The term combines the Greek-derived combining form lyophil-, associated with a substance's affinity for water, with the suffix -isation, meaning the process of making or performing an action. The underlying idea comes from the Greek roots lyo-, meaning loose or dissolved, and philos, meaning loving. The English technical vocabulary developed from these roots through the study of substances that favour or retain water and of methods for removing it.
Related word forms
How lyophilisation is actually used
This is the standard British spelling. The form is primarily used in technical and scientific contexts, particularly food preservation, pharmaceuticals, and biological research; American English generally uses lyophilization.
Easily confused with lyophilisation
Evaporation removes water as liquid or vapour at ordinary or elevated temperatures, whereas lyophilisation removes it by freezing the material and sublimating the ice under vacuum.
Dehydration is the general removal or loss of water, while lyophilisation is a specific preservation technique involving freezing and sublimation.