Packaging and storage
Preserve in tight, light-resistant containers.
Specific rotation
781S
:
between +95
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and +97
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, from optical rotation measurements made immediately following the preparation of the
Test solution.
Test solution:
50 mg per mL, in carbon dioxide-free water.
pH
791
:
between 6.8 and 7.4 in a solution (1 in 10).
Loss on drying
731
Dry an accurately weighed quantity of about 3 g of it at 105
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for 2 hours: it loses not more than 0.1% of its weight.
Assay
Transfer an accurately weighed quantity of about 300 mg of Calcium Ascorbate to a 250-mL conical flask. Add 50 mL of water, mix to dissolve, and immediately titrate with 0.1
N iodine VS, adding 3 mL of
starch TS as the endpoint is approached. Each mL of 0.1
N iodine is equivalent to 10.66 mg of C
12H
14CaO
12·2H
2O.
Auxiliary Information
Staff Liaison :
Lawrence Evans, III, Ph.D., Scientist
Expert Committee : (DSN05) Dietary Supplements - Non-Botanicals
USP29NF24 Page 345
Pharmacopeial Forum : Volume No. 27(6) Page 3255
Phone Number : 1-301-816-8389