C
6H
10CaO
6·
xH
2O
(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].
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).
Identification
A:
A solution (1 in 20) responds to the tests for
Calcium 191.
B:
To 10 mg add 1 mL of sulfuric acid, and heat for 2 minutes in a water bath maintained at a temperature of 85
. Cool the solution to room temperature, add about 10 mg of 4-phenylphenol crystals, swirl, and allow to stand for about 20 minutes: a violet color develops that deepens with the passage of time.
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.
Auxiliary Information
Staff Liaison :
Lawrence Evans, III, Ph.D., Scientist
Expert Committee : (DSN05) Dietary Supplements - Non-Botanicals
USP29NF24 Page 356
Pharmacopeial Forum : Volume No. 27(6) Page 3259
Phone Number : 1-301-816-8389