Packaging and storage— Preserve in tight containers, and prevent exposure to excessive heat.

Acid-consuming capacity— Transfer about 0.2 g of Magnesium Aluminosilicate, accurately weighed, to a glass-stoppered flask, and add 100.0 mL of 0.1 N hydrochloric acid VS. Stopper the flask tightly, shake at 37 ± 2 for 1 hour, and filter. Transfer 50.0 mL of the filtrate to a beaker, and, while stirring, titrate the excess hydrochloric acid with 0.1 N sodium hydroxide VS to attain a pH of 3.5. Perform a blank determination, and make any necessary correction: not less than 250 mL of 0.1 N hydrochloric acid is consumed per g of Magnesium Aluminosilicate, calculated on the dried basis.

pH 791— Transfer 2 g of Magnesium Aluminosilicate to a suitable container, and add 50 mL of water. While stirring, immerse the pH electrodes in the suspension, and after 2 minutes record the pH: between 8.5 and10.5.

Residual solvents 467: meets the requirements.

Other requirements— It meets the requirements for Identification, Loss on drying, Soluble salts, Alkalinity, Chloride, Sulfate, Arsenic, Iron, and Heavy metals under Magnesium Aluminometasilicate.

Assay for aluminum oxide, magnesium oxide, and silicon dioxide— Proceed as directed in the Assay for aluminum oxide, the Assay for magnesium oxide, and the Assay for silicon dioxide under Magnesium Aluminometasilicate.

Expert Committee : (EM105) Excipient Monographs 1

USP29–NF24 Page 3362

Phone Number : 1-301-816-8262