Microparticle

Microparticles are particles between 0.1 and 100 μm in size. Commercially available microparticles are available in a wide variety of materials, including ceramics, glass, polymers, and metals. Microparticles encountered in daily life include pollen, sand, dust, flour, and powdered sugar. Microparticles have a much larger surface-to-volume ratio than at the macroscale, and thus their behavior can be quite different. For example, metal microparticles can be explosive in air. Microspheres are spherical microparticles, and are used where consistent and predictable particle surface area is important. In biological systems, a microparticle is synonymous with a microvesicle, a type of extracellular vesicle (EV). Mathematical: as the term "micro" refers to , the range for micro would then be to , or roughly 31.6 nm to 31.6 micrometers. However, general acceptance considers particles smaller than 100 nm nanoparticles. Rounding: rules of rounding in mathematics provide an alternative for the definition. Anything larger than 0.5 μm and anything smaller than 0.5 mm is considered microparticles. Convenient/popular: Very often particles with dimensions more than 100 nm are still called nanoparticles. The upper range may be between 300 and 700 nm, so this would give a size definition for microparticles of 0.3 to 300 μm or 0.7 to 700 micrometers. Home pregnancy tests make use of gold microparticles. Many applications are also listed in the microsphere article. A recent study showed that infused, negatively charged, immune-modifying microparticles could have therapeutic use in diseases caused or potentiated by inflammatory monocytes. Microspheres are small spherical particles, with diameters in the micrometer range (typically 1 μm to 1000 μm (1 mm). Microspheres are sometimes referred to as spherical microparticles. In general microspheres are solid or hollow and do not have a fluid inside, as opposed to microcapsules. Microspheres can be made from various natural and synthetic materials.