Carboxymethylcellulose calcium occurs as a white to yellowishwhite, hygroscopic, odorless powder
- BP: Carmellose Calcium
- JP: Carmellose Calcium
- PhEur: Carmellose Calcium
- USP-NF: Carboxymethylcellulose Calcium
Calcium carboxymethylcellulose; calcium cellulose glycolate; carmellosum calcium; CMC calcium; ECG 505; Nymcel ZSC.
Chemical Name and CAS Registry Number: Cellulose, carboxymethyl ether, calcium salt [9050-04-8]
Empirical Formula and Molecular Weight: The USP32–NF27 describes carboxymethylcellulose calcium as the calcium salt of a polycarboxymethyl ether of cellulose.
Emulsifying agent; coating agent; stabilizing agent; suspending agent; tablet and capsule disintegrant; viscosity-increasing agent; water-absorbing agent.
Applications in Pharmaceutical Formulation or Technology
The main use of carboxymethylcellulose calcium is in tablet formulations, where it is used as a binder, diluent, and disintegrant. Although carboxymethylcellulose calcium is insoluble in water, it is an effective tablet disintegrant as it swells to several times its original bulk on contact with water. Concentrations up to 15% w/w may be used in tablet formulations; above this concentration, tablet hardness is reduced.
Carboxymethylcellulose calcium is also used in other applications similarly to carboxymethylcellulose sodium; for example, as a suspending or viscosity-increasing agent in oral and topical pharmaceutical formulations. Carboxymethylcellulose calcium is also used in modern wound dressings for its water absorption, retention and hemostatic properties.
Method of Manufacture
Cellulose, obtained from wood pulp or cotton fibers, is carboxymethylated, followed by conversion to the calcium salt. It is then graded on the basis of its degree of carboxymethylation and pulverized.
Carboxymethylcellulose sodium; croscarmellose sodium.