Ascorbic Acid
176.12l-Ascorbic acid.
l-Ascorbic acid
[50-81-7].» Ascorbic Acid contains not less than 99.0 percent and not more than 100.5 percent of C6H8O6.
Packaging and storage—
Preserve in tight, light-resistant containers.
Identification—
B:
A solution (1 in 50) reduces alkaline cupric tartrate TS slowly at room temperature but more readily upon heating.
Specific rotation 
781S
:
between +20.5
and +21.5, the optical rotation being measured immediately, following the preparation of the solution.
781S:
between +20.5 and +21.5, the optical rotation being measured immediately, following the preparation of the solution.
Test solution:
100 mg per mL, in carbon dioxide-free water.
Residue on ignition 281:
not more than 0.1%.
281:
not more than 0.1%.
Heavy metals 231—
Dissolve 1 g in 25 mL of water: the limit is 0.002%.
231—
Dissolve 1 g in 25 mL of water: the limit is 0.002%.
Assay—
Dissolve about 400 mg of Ascorbic Acid, accurately weighed, in a mixture of 100 mL of water and 25 mL of 2 N sulfuric acid. Add 3 mL of starch TS, and titrate at once with 0.1 N iodine VS. Each mL of 0.1 N iodine is equivalent to 8.806 mg of C6H8O6.
Auxiliary Information—
Please check for your question in the FAQs before contacting USP.
Chromatographic Column—
| 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 1580
Chromatographic columns text is not derived from, and not part of, USP 32 or NF 27.