Calcium Carbonate Oral Suspension
» Calcium Carbonate Oral Suspension contains not less than 90.0 percent and not more than 110.0 percent of the labeled amount of calcium carbonate (CaCO3).
Packaging and storage— Preserve in tight containers, and avoid freezing.
Identification— The addition of acetic acid to it produces effervescence, and the resulting solution, after being boiled, responds to the tests for Calcium 191.
Microbial enumeration tests 61 and Tests for specified microorganisms 62 Its total aerobic microbial count does not exceed 100 cfu per mL, and it meets the requirements of the test for absence of Escherichia coli and Pseudomonas aeruginosa.
pH 791: between 7.5 and 8.7.
Other requirements— It meets the requirements of the tests for Limit of fluoride, Arsenic, Lead, and Heavy metals under Calcium Carbonate, portions of Oral Suspension adequate to provide quantities of calcium carbonate equivalent to the stated amounts of test specimen being used.
Assay— Transfer an accurately measured quantity of Oral Suspension, previously shaken in its original container, equivalent to about 1 g of calcium carbonate, to a beaker with the aid of 25 mL of water, and add 20 mL of 1 N hydrochloric acid. Heat on a steam bath for 30 minutes, allow to cool, transfer with the aid of water to a 100-mL volumetric flask, dilute with water to volume, mix, and filter. Transfer 20.0 mL of the filtrate to a suitable container, dilute with water to 100 mL, add 15 mL of 1 N sodium hydroxide, 5 mL of triethanolamine, and 100 mg of hydroxy naphthol blue, and titrate with 0.05 M edetate disodium VS until the solution is deep blue. Each mL of 0.05 M edetate disodium is equivalent to 5.004 mg of calcium carbonate (CaCO3).
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Topic/Question Contact Expert Committee
Monograph Curtis Phinney

1-301-816-8345
(DSN05) Dietary Supplements - Non-Botanicals
61 Radhakrishna S Tirumalai, Ph.D.
Senior Scientist
1-301-816-8345
(MSA05) Microbiology and Sterility Assurance
62 Radhakrishna S Tirumalai, Ph.D.
Senior Scientist
1-301-816-8345
(MSA05) Microbiology and Sterility Assurance
USP32–NF27 Page 1755
Pharmacopeial Forum: Volume No. 27(6) Page 3255