Calcium Gluconate Tablets
» Calcium Gluconate Tablets contain not less than 95.0 percent and not more than 105.0 percent of the labeled amount of calcium gluconate (C12H22CaO14).
Packaging and storage— Preserve in well-closed containers.
USP Reference standards 11
USP Potassium Gluconate RS
Identification— A warm, filtered solution of Tablets, equivalent to calcium gluconate solution (1 in 10), diluted with water, where necessary, responds to the Identification tests under Calcium Gluconate.
Dissolution 711
Medium: water; 900 mL.
Apparatus 2: 50 rpm.
Time: 45 minutes.
Procedure— Determine the amount of C12H22CaO14 dissolved, employing atomic absorption spectrophotometry at a wavelength of about 422.8 nm on filtered portions of the solution under test, suitably diluted with water, in comparison with a Standard solution having a known concentration of calcium in the same Medium.
Tolerances— Not less than 75% (Q) of the labeled amount of C12H22CaO14 is dissolved in 45 minutes.
Uniformity of dosage units 905: meet the requirements.
Assay— Weigh and finely powder not fewer than 20 Tablets. Transfer an accurately weighed portion of the powder, equivalent to about 500 mg of calcium gluconate, to a suitable crucible, and ignite, gently at first, until free from carbon. Cool the crucible, add 10 mL of water, and dissolve the residue by adding sufficient 3 N hydrochloric acid, dropwise, to achieve complete solution. Transfer the solution to a suitable container, dilute with water to 150 mL, and while stirring, preferably with a magnetic stirrer, add about 20 mL of 0.05 M edetate disodium VS from a 50-mL buret. Add 15 mL of 1 N sodium hydroxide and 300 mg of hydroxy naphthol blue, and continue the titration to a blue endpoint. Each mL of 0.05 M edetate disodium is equivalent to 21.52 mg of calcium gluconate (C12H22CaO14).
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Topic/Question Contact Expert Committee
Monograph Curtis Phinney

(DSN05) Dietary Supplements - Non-Botanicals
Reference Standards Lili Wang, Technical Services Scientist
711 Margareth R.C. Marques, Ph.D.
Senior Scientist
(BPC05) Biopharmaceutics05
USP32–NF27 Page 1765
Pharmacopeial Forum: Volume No. 27(6) Page 3258