Calcium Ascorbate
C12H14CaO12·2H2O
426.34
»Calcium Ascorbate contains not less than 98.0percent and not more than 101.0percent of C12H14CaO12·2H2O,calculated on the as-is basis.
Packaging and storage—
Preserve in tight,light-resistant containers.
Identification—
A:
Asolution (1in 10)responds to the tests for Calcium á191ñ.
B:
Asolution (1in 10)decolorizes a solution of dichlorophenol-indophenol (1in 10).
C:Infrared Absorption á197Mñ.
Specific rotation á781Sñ:
between +95
and +97,from optical rotation measurements made immediately following the preparation of the Test solution.
and +97,from optical rotation measurements made immediately following the preparation of the Test solution.
Test solution:
50mg per mL,in carbon dioxide-free water.
pHá791ñ:
between 6.8and 7.4in a solution (1in 10).
Loss on drying á731ñ—
Dry an accurately weighed quantity of about 3g of it at 105for 2hours:it loses not more than 0.1%of its weight.
for 2hours:it loses not more than 0.1%of its weight.
Arsenic,Method Iá211ñ:
3µg per g.
Heavy metals,Method IIá231ñ:
0.001%.
Limit of fluoride—
Proceed as directed in the test for Limit of fluorideunder Dibasic Calcium Phosphate:the limit is 10ppm.
Assay—
Transfer an accurately weighed quantity of about 300mg of Calcium Ascorbate to a 250-mLconical flask.Add 50mLof water,mix to dissolve,and immediately titrate with 0.1Niodine VS,adding 3mLof starch TSas the endpoint is approached.Each mLof 0.1Niodine is equivalent to 10.66mg of C12H14CaO12·2H2O.
Auxiliary Information—
Staff Liaison:Lawrence Evans,III,Ph.D.,Scientist
Expert Committee:(DSN)Dietary Supplements:Non-Botanicals
USP28–NF23Page 318
Pharmacopeial Forum:Volume No.27(6)Page 3255
Phone Number:1-301-816-8389