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Powdered cellulose occurs as a white or almost white, odorless and tasteless powder of various particle sizes, ranging from a free flowing fine or granular dense powder, to a coarse, fluffy, non-flowing material.
Nonproprietary Names
- BP: Powdered Cellulose
- JP: Powdered Cellulose
- PhEur: Cellulose, Powdered
- USP-NF: Powdered Cellulose
Synonyms
Alpha-cellulose; Arbocel; cellulosi pulvis; E460; Elcema; KC Flock; Microcel 3E-150; Sanacel; Sanacel Pharma; Sancel-W; Solka-Floc.
Chemical Name and CAS Registry Number: Cellulose [9004-34-6]
Empirical Formula and Molecular Weight: (C6H10O5)n =243 000 where n = 500. Since cellulose is derived from a natural polymer, it has variable chain length and thus variable molecular weight
Functional Category
Adsorbent; glidant; suspending agent; tablet and capsule diluent; tablet disintegrant; thickening agent.
Applications in Pharmaceutical Formulation or Technology
Powdered cellulose is used as a tablet diluent and filler in two-piece hard capsules. In both contexts it acts as a bulking agent to increase the physical size of the dosage form for formulations containing a small amount of active substance.
Powdered cellulose has acceptable compression properties, although the flow properties of most brands are poor. However, low-crystallinity powdered cellulose has exhibited properties that are different from standard powdered cellulose materials, and has shown potential as a direct-compression excipient.
In soft gelatin capsules, powdered cellulose may be used to reduce the sedimentation rate of oily suspension fills. It is also used as the powder base material of powder dosage forms, and as a suspending agent in aqueous suspensions for peroral delivery. It may also be used to reduce sedimentation during the manufacture of suppositories.
Powdered cellulose has been investigated as an alternative to microcrystalline cellulose as an agent to assist the manufacture of pellets by extrusion/spheronization. However, powdered cellulose alone requires too much water and due to water movement during extrusion cannot be used as an extrusion/spheronization aid on its own. Powdered cellulose is also used widely in cosmetics and food products as an adsorbent and thickening agent.
Method of Manufacture
Powdered cellulose is manufactured by the purification and mechanical size reduction of a-cellulose obtained as a pulp from fibrous plant materials.
