Starch carboxymethyl ether, sodium salt.

Packaging and storage— Preserve in well-closed containers, preferably protected from wide variations in temperature and humidity, which may cause caking.

Labeling— The labeling indicates the pH range.

Identification— A slightly acidified solution of it is colored blue by iodine and potassium iodide TS 1.

Microbial limits 61— It meets the requirements of the tests for absence of Salmonella species and Escherichia coli.

pH 791— Disperse 1 g in 30 mL of water: the pH of the resulting suspension is either between 3.0 and 5.0 or between 5.5 and 7.5.

Loss on drying 731— Dry it at 130 for 90 minutes: it loses not more than 10.0% of its weight.

Iron 241: 0.002%, the Test Preparation being prepared as directed for Test Preparation under Heavy metals, Method III 231, a 0.5-g test specimen being used and the final solution being diluted with water to 47 mL.

Heavy metals, Method II 231: 0.002%.

Sodium chloride— Weigh accurately about 1 g, transfer to a conical flask, add 20 mL of 80% alcohol, 0.1 mL of phenolphthalein TS, and 1 N sodium hydroxide solution until the suspension becomes faintly pink, stir for 10 minutes, and filter. Repeat the extraction until chloride has been completely extracted, as shown by a test with silver nitrate TS. Dry the insoluble portion at 105 to constant weight (A mg), and reserve it for the Assay. Evaporate the combined filtrates, and dry the residue at 105 to constant weight. The weight of the dried residue is not greater than 15% of the weight of Sodium Starch Glycolate taken. If the weight of the dried residue is not more than 7.0% of the weight of Sodium Starch Glycolate taken, the requirement is met. If the weight is greater than 7.0% of the weight of Sodium Starch Glycolate taken, transfer it with the aid of water to a 200-mL volumetric flask, add 5 mL of nitric acid and 40.0 mL of 0.1 N silver nitrate VS, mix, and dilute with water to volume. Allow it to stand in the dark for 30 minutes, and filter. To 100.0 mL of the filtrate add 5 mL of ferric ammonium sulfate TS, and titrate with 0.1 N ammonium thiocyanate VS (see Residual Titrations under Titrimetry 541). Calculate the percentage of sodium chloride by the formula: in which N1 and N2 are the normalities of the silver nitrate VS and the ammonium thiocyanate VS, respectively; V is the volume, in mL, of ammonium thiocyanate VS used in the titration; and W is the weight, in g, of Sodium Starch Glycolate taken.

Residual solvents 467: meets the requirements.

Assay— Transfer an accurately weighed portion, B, (about 700 mg) of the dried 80% alcohol-insoluble portion obtained in the test for Sodium chloride, to a suitable flask, add 80 mL of glacial acetic acid, heat the mixture under reflux, on a boiling water bath, for 2 hours, cool to room temperature, and titrate with 0.1 N perchloric acid VS, determining the endpoint potentiometrically. Calculate the percentage of sodium combined in the form of sodium starch glycolate by the formula: in which V3 is the volume, in mL, of the perchloric acid VS; N3 is the normality of the perchloric acid VS; and B is the weight, in mg, of the dried alcohol-insoluble residue taken for the Assay.

Expert Committee : (EM205) Excipient Monographs 2

USP29–NF24 Page 3426

Phone Number : 1-301-816-8351