Carboxymethylcellulose Calcium

Cellulose, carboxymethyl ether, calcium salt.
Cellulose carboxymethyl ether calcium salt [9050-04-8].
» Carboxymethylcellulose Calcium is the calcium salt of a polycarboxymethyl ether of cellulose.
Packaging and storage— Preserve in tight containers.
Identification—
A: Shake thoroughly 0.1 g with 10 mL of water, followed by 2 mL of 1 N sodium hydroxide, allow to stand for 10 minutes, and use 1 mL of this solution as the test solution, retaining the remainder of it for Identification tests B and C. To 1 mL of the test solution add water to make 5 mL, then to 1 drop of the resulting solution add 0.5 mL of chromotropic acid TS, and heat in a water bath for 10 minutes: a red-purple color develops.
B: Shake 5 mL of the test solution obtained in Identification test A with 10 mL of acetone: a white flocculent precipitate is formed.
C: Shake 5 mL of the test solution obtained in Identification test A with 1 mL of ferric chloride TS: a brown, flocculent precipitate is formed.
D: Ignite 1 g to ash, dissolve the residue in 10 mL of water and 5 mL of 6 N acetic acid, and filter, if necessary. Boil the filtrate, cool, and neutralize with 6 N ammonium hydroxide: the solution responds to the tests for Calcium 191.
Alkalinity— Shake thoroughly 1.0 g with 50 mL of freshly boiled and cooled water, and add 2 drops of phenolphthalein TS: no red color develops.
Loss on drying 731 Dry it at 105º for 4 hours: it loses not more than 10.0% of its weight.
Residue on ignition 281: between 10.0% and 20.0%, about 1.0 g, previously dried, being used for the test.
Heavy metals, Method II 231: 0.002%, adding 1 mL of hydroxylamine hydrochloride solution (1 in 5) to the solution of the residue.
Limit of chloride 221 Shake thoroughly 0.80 g with 50 mL of water, dissolve in 10 mL of 1 N sodium hydroxide, add water to make 100 mL, and use 20 mL of this solution as the test solution, retaining the remainder of it for the test for Limit of sulfate. Heat 20 mL of the test solution with 10 mL of 2 N nitric acid in a water bath until a flocculent precipitate is formed, cool, centrifuge, and remove the supernatant. Wash the precipitate with three 10-mL portions of water by centrifuging each time, combine the supernatant and the washings, add water to make 100 mL, and mix: a 25-mL portion of this solution shows no more chloride than is contained in 0.20 mL of 0.020 N hydrochloric acid (0.36%).
Limit of sulfate 221 Heat 10 mL of the test solution obtained in test for Limit of chloride with 1 mL of hydrochloric acid in a water bath until a flocculent precipitate is formed, cool, centrifuge, and remove the supernatant. Wash the precipitate with three 10-mL portions of water by centrifuging each time, combine the supernatant and the washings, add water to make 100 mL, and mix: a 25-mL portion of this solution shows no more sulfate than is contained in 0.21 mL of 0.020 N sulfuric acid (1.0%).
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Topic/Question Contact Expert Committee
Monograph Kevin T. Moore, Ph.D.
Scientist
1-301-816-8369
(EM205) Excipient Monographs 2
USP32–NF27 Page 1193
Pharmacopeial Forum: Volume No. 31(5) Page 1420
Chromatographic Column—
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.