micella
Definition
- Noun (Chemistry, Biology):
- A colloidal particle: "micella" refers to a submicroscopic aggregate of molecules (such as surfactants, soaps, or lipids) dispersed in a liquid, typically forming a spherical or layered structure. In biological contexts, it often describes the structural unit of certain cell membranes or protein complexes.
Usage Examples
Chemistry context:
- The soap molecules form a micella when dissolved in water, trapping grease inside. (A colloidal aggregate that helps in cleaning.)
Biology context:
- The micella in the cell membrane helps regulate the passage of substances. (A structural unit of a membrane.)
Advanced Usage
"Micellar solution": a liquid containing micelles, often used in detergents or drug delivery.
- The micellar solution improves the solubility of hydrophobic drugs. (A solution with suspended micelles.)
"Micellar catalysis": the acceleration of chemical reactions within micelles.
- Micellar catalysis is used to speed up organic reactions in water. (Reactions enhanced by micelle formation.)
Variants and Related Words
Micelle (n): a more common spelling of "micella," referring to the same colloidal structure.
- The micelle forms when the concentration of surfactant exceeds the critical micelle concentration. (A synonym for micella.)
Micellar (adj): relating to or consisting of micelles.
- The micellar structure is crucial for emulsification. (Pertaining to micelles.)
Synonyms
- Colloidal aggregate: a cluster of molecules dispersed in a medium.
- Surfactant aggregate: a group of surface-active molecules.
Related Idioms
- "Critical micelle concentration" (CMC): the minimum concentration at which micelles begin to form.
- Above the CMC, the solution becomes a micellar system. (A threshold in surfactant chemistry.)
Notes
- The term "micella" is less common than "micelle" in modern English, but both refer to the same concept. It is primarily used in technical chemistry and biology texts.