Tactoids are

liquid crystal Liquid crystal (LC) is a state of matter whose properties are between those of conventional liquids and those of solid crystals. For example, a liquid crystal may flow like a liquid, but its molecules may be oriented in a crystal-like way. The ...

microdomains nucleated in isotropic phases, which can be distinguished as spherical or spindle-shaped

birefringent Birefringence is the optics, optical property of a material having a refractive index that depends on the Polarization (waves), polarization and propagation direction of light. These optically anisotropic materials are said to be birefringent (or ...

microdroplets under

polarized light microscopy Polarized light microscopy can mean any of a number of optical microscopy techniques involving polarized light Polarization ( also polarisation) is a property applying to transverse waves that specifies the geometrical orientation of the osci ...

. Tactoids are a transition state between isotropic and

macroscopic The macroscopic scale is the length scale on which objects or phenomena are large enough to be visible with the naked eye, without magnifying optical instruments. It is the opposite of microscopic. Overview When applied to physical phenomena ...

liquid crystalline phases. The first observation of tactoids was made by Zocher in 1925, when he studied the

nematic Liquid crystal (LC) is a state of matter whose properties are between those of conventional liquids and those of solid crystals. For example, a liquid crystal may flow like a liquid, but its molecules may be oriented in a crystal-like way. The ...

phase formed in

vanadium pentoxide Vanadium(V) oxide (''vanadia'') is the inorganic compound with the formula V2 O5. Commonly known as vanadium pentoxide, it is a brown/yellow solid, although when freshly precipitated from aqueous solution, its colour is deep orange. Because ...

sol Sol or SOL may refer to: Astronomy * The Sun Currency * SOL Project, a currency project in France * French sol, or sou * Argentine sol * Bolivian sol, the currency of Bolivia from 1827 to 1864 * Peruvian sol, introduced in 1991 * Peruvian sol ( ...

s. After that, tactoids have been found in the

phase transition In chemistry, thermodynamics, and other related fields, a phase transition (or phase change) is the physical process of transition between one state of a medium and another. Commonly the term is used to refer to changes among the basic states ...

processes in many lyotropic liquid crystalline substances, such as

tobacco mosaic virus ''Tobacco mosaic virus'' (TMV) is a positive-sense single-stranded RNA virus species in the genus '' Tobamovirus'' that infects a wide range of plants, especially tobacco and other members of the family Solanaceae. The infection causes charact ...

polypeptides Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. ...

, and cellulose nanocrystals.

In biology

It has been shown that

filamin Filamins are a class of proteins that hold two actin filaments at large angles. Filamin protein in mammals is made up of an actin-binding domain at its N-terminus that is followed by 24 immunoglobulin-like repeat modules of roughly 95 amino acids. ...

causes

actin Actin is a protein family, family of Globular protein, globular multi-functional proteins that form microfilaments in the cytoskeleton, and the thin filaments in myofibril, muscle fibrils. It is found in essentially all Eukaryote, eukaryotic cel ...

to condense into tactoids.

References

Biochemistry Chemical properties Liquid crystals {{material-stub