Packaging and storage—
Preserve in tight, light-resistant containers.
Identification—
B: Ultraviolet Absorption 
197U
—
Solution:
35 µg per mL.
Medium:
pH 12.0 buffer (prepared from 7.46 g of potassium chloride and 24 mL of 1 N sodium hydroxide dissolved in 2000 mL of water).
Absorptivities at 279 nm, calculated on the dried basis for the test sample only, do not differ by more than 2.0%.
Loss on drying 731—
Dry about 500 mg, accurately weighed, in vacuum at 60
for 2 hours: it loses not more than 1.0% of its weight.
Assay—
Dissolve about 250 mg of Idoxuridine, accurately weighed, in 20 mL of dimethylformamide that previously has been neutralized with 0.1 N sodium methoxide in toluene VS, a solution of 300 mg of thymol blue in 100 mL of methanol being used as the indicator. Titrate with 0.1 N sodium methoxide in toluene VS to a blue endpoint, taking precautions against absorption of atmospheric carbon dioxide. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N sodium methoxide is equivalent to 35.41 mg of C9H11IN2O5.
Auxiliary Information—
Staff Liaison :
Behnam Davani, Ph.D., MBA, Senior Scientist
Expert Committee : (MDAA05) Monograph Development-Antivirals and Antimicrobials
USP29–NF24 Page 1106
Pharmacopeial Forum : Volume No. 29(4) Page 1033
Phone Number : 1-301-816-8394
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