Microcapsules are referred to as microcapsules, which are tiny particles of solid, liquid, or stick suspension (called capsule core material) surrounded by a layer of film (called packaging material) to form extremely tiny capsules, the diameter of which ranges from 0.0 microns to 5,000 microns. Micron. Microcapsules used for medicine were initially used externally, and then developed into oral administration and internal muscle tissue.        Microcapsules used in medicine are mainly slow-release microcapsules, that is, the active molecules of drugs are combined with macromolecular carriers and put into biological activity. Through diffusion and penetration in the body, the active molecules of the drug are released at an appropriate concentration and duration, so as to achieve the purpose of fully exerting the drug effect.

      Microcapsules are developed on the basis of traditional capsules. In the late 1940s, the American Wurster first used the air suspension method to obtain microcapsules and successfully applied them to medicines. At present, microcapsules in medicine mainly study the application of microcapsules in controlled release and targeting functions of drugs and the biodegradability of microcapsules.

     In the field of medicine, the purpose of micro-encapsulation of medicines is mainly to cover up the bad smell and taste of oral medicines, improve the stability of medicines, prevent medicines from being in the stomach or reduce the irritation to the stomach, and make liquid medicines solidified to facilitate the Use and storage, improve the dissolution rate and bioavailability of preparations, facilitate the compatibility of compound medicines, make medicines have sustained-release or controlled-release properties, improve the curative effect, and make medicines targeted.