C6H10CaO6·xH2O
(anhydrous) 218.22

Propanoic acid, 2-hydroxy-, calcium salt (2:1), hydrate.
Calcium lactate (1:2) hydrate [41372-22-9].

Calcium lactate (1:2) pentahydrate. 308.30 [5743-47-5].

Anhydrous [814-80-2].

Packaging and storage— Preserve in tight containers.

Labeling— The label indicates whether it is the dried form or is hydrous; if the latter, the label indicates the degree of hydration. Where the quantity of Calcium Lactate is indicated in the labeling of any preparation containing Calcium Lactate, this shall be understood to be in terms of calcium lactate pentahydrate (C6H10CaO6·5H2O).

USP Reference standards 11—
USP Calcium Lactate RS .

Identification—

Acidity— Titrate 20 mL of a solution (1 in 20) with 0.10 N sodium hydroxide, using phenolphthalein TS as the indicator: not more than 0.50 mL is required for neutralization (0.45% as lactic acid).

Loss on drying 731— Distribute a 1- to 2-g portion evenly in a suitable weighing dish to a depth of not more than 3 mm, and dry at 120 for 4 hours: the pentahydrate loses between 22.0% and 27.0% of its weight; the trihydrate loses between 15.0% and 20.0% of its weight; the monohydrate loses between 5.0% and 8.0% of its weight; and the dried form loses not more than 3.0% of its weight.

Volatile fatty acid— Stir about 500 mg with 1 mL of sulfuric acid, and warm: the mixture does not emit an odor of volatile fatty acid.

Heavy metals 231— Dissolve 1 g in 2.5 mL of 1 N acetic acid, and dilute with water to 25 mL: the limit is 0.002%.

Limit of magnesium and alkali salts— Mix 1.0 g with 40 mL of water, carefully add 1 mL of hydrochloric acid, and heat the solution to boiling. Proceed as directed in the test for Magnesium and alkali salts under Calcium Carbonate, beginning with “Rapidly add 40 mL of oxalic acid TS”: the weight of the residue does not exceed 5.0 mg (1.0%).

Assay— Transfer an accurately weighed amount of Calcium Lactate, equivalent to about 350 mg of C6H10CaO6, to a suitable container, and dissolve in a mixture of water and 3 N hydrochloric acid (150:2). While stirring, preferably with a magnetic stirrer, add about 30 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 10.91 mg of C6H10CaO6.

Topic/Question	Contact	Expert Committee
Monograph	Curtis Phinney 1-301-816-8540	(DSN05) Dietary Supplements - Non-Botanicals
Reference Standards	Lili Wang, Technical Services Scientist 1-301-816-8129 RSTech@usp.org

USP32–NF27 Page 1766

CALCIUM LACTATE

Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.