In the pharmaceutical industry, Microcrystalline cellulose (MCC) is mainly used for two aspects. One is to use the property of easily forming gels in water with vigorous stirring for preparing paste and suspension drugs. The other is to use its molding action for excipients of pharmaceutical tableting.
Methyl cellulose (MC) is a methyl ether of cellulose, a widely used pharmaceutical excipient, safe to be taken orally and non-toxic. It cannot be absorbed in the intestine and can be used as a binder of tablets. Furthermore, it has the function of improving disintegration and dissolution. It can be used for suspending, thickening and emulsion stability of liquid pharmaceuticals, and for film coating materials of low viscosity aqueous solution.
Ethyl cellulose (EC) is a ethyl ether of cellulose, and has a variety of uses in the medicine. It can be used as the binder of tablets, the film coating material, or as the matrix material for preparing various types of matrix sustained-release tablets, the mixed material film for preparing coated sustained-release preparations and pellets, the encapsulating excipient for preparing sustained-release microcapsules, and also as the carrier material for preparing the solid dispersion. EC dispersion of 30% is commonly used for coating film abroad.
The aqueous solution of hydroxypropyl cellulose (HPC) has better coating effects than that of MC, but during coating it is easy to get sticky and difficult to control. Adding a little talcum powder helps to improve the situation.
Hydroxy propyl methyl cellulose (HPMC) is a non-ionic cellulose mixed ether, with emulsifying, thickening, suspending, thickening, bonding, gelling and film-forming properties, and can be used as adhesives, disintegrating agents, sustained (controlled) release agents, coating film-forming agents.
In the medicine, there are a wide range of uses, especially as excipients for sustained or controlled release formulations. HPMC has been included in the GRAS (materials generally accepted as safe). It has been accepted as a food additive in Europe and listed in the Inactive Ingredient Guide of FDA.