Calcium Glubionate Syrup
» Calcium Glubionate Syrup is a solution containing equimolar amounts of Calcium Gluconate and Calcium Lactobionate or with Calcium Lactobionate predominating. It contains not less than 95.0 percent and not more than 105.0 percent of the labeled amount of calcium (Ca).
Packaging and storage— Preserve in tight containers, at a temperature not exceeding 30, and avoid freezing.
A: A dilution of the Syrup with water (1 in 10) responds to the tests for Calcium 191.
B: Dilute a portion of the Syrup with water to obtain a test solution containing about 0.4 mg of calcium per mL. Prepare a Standard solution in water containing 2 mg of calcium gluconate and 4 mg of calcium lactobionate per mL. Apply separately 5 µL of the test solution and 5 µL of the Standard solution to a suitable thin-layer chromatographic plate coated with 0.25-mm layer of chromatographic silica gel (see Chromatography 621). Dry the plate in a current of cool air. Place the plate in a suitable chromatographic chamber lined with filter paper and previously equilibrated with a solvent system consisting of a mixture of alcohol, water, ethyl acetate, and ammonium hydroxide (50:30:10:10). Develop the chromatogram until the solvent front has moved about three-fourths of the length of the plate. Remove the plate from the chamber, and dry at 100 for 20 minutes. Allow to cool, and spray with a spray reagent prepared as follows: Dissolve 2.5 g of ammonium molybdate in about 50 mL of 2 N sulfuric acid in a 100-mL volumetric flask, add 1.0 g of ceric sulfate, swirl to dissolve, dilute with 2 N sulfuric acid to volume, and mix. Heat the plate at 110 for about 10 minutes: the two principal spots obtained from the test solution correspond in color, size, and RF value to those obtained from the Standard solution. [note—Sucrose, if present in the test solution, appears in the chromatogram as a spot between two principal spots.]
pH 791: between 3.4 and 4.5.
Assay— Transfer an accurately measured portion of Syrup, equivalent to about 70 mg of Ca, to a suitable beaker. Add 2 mL of 3 N hydrochloric acid, and dilute with water to about 150 mL. While stirring 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 2.004 mg of calcium (Ca).
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Monograph Daniel K. Bempong, Ph.D.
Senior Scientist
(MDPS05) Monograph Development-Pulmonary and Steroids
USP32–NF27 Page 1762
Pharmacopeial Forum: Volume No. 27(6) Page 3257