Nitrofurazone Topical Solution
»Nitrofurazone Topical Solution contains not less than 95.0percent and not more than 105.0percent (w/w)of the labeled amount of C6H6N4O4.
NOTE—Avoid exposure at all times to direct sunlight,excessive heat,and alkaline materials.
Packaging and storage— Preserve in tight,light-resistant containers.Avoid exposure to direct sunlight and excessive heat.
Identification— Dissolve 400mg of potassium hydroxide in a mixture of 9.5mLof alcohol and 0.5mLof methanol.Immediately before use dilute with dimethylformamide to 100mL.To 10mLof this solution add 1drop of Topical Solution:a purple solution results.
Assay— [NOTE—Protect from light all solutions that contain nitrofurazone.]
Triethylamine buffer,Mobile phase,Standard preparation,andChromatographic system— Proceed as directed in the Assayunder Nitrofurazone Ointment.
Assay preparation— Transfer an accurately measured portion of Topical Solution,equivalent to about 1mg of nitrofurazone,to a 100-mLlow actinic volumetric flask.Add 0.2mLof dimethylformamide and about 25mLof warm (between 40and 50)alcohol.Dilute with water to volume,and mix.
Procedure— Proceed as directed in the Assayunder Nitrofurazone Ointment.Calculate the quantity,in mg,of C6H6N4O4in the portion of Topical Solution taken by the formula:
100C(rU/rS),
in which Cis the concentration,in mg per mL,of USP Nitrofurazone RSin the Standard preparation,and rUand rSare the nitrofurazone peak responses obtained from the Assay preparationand the Standard preparation,respectively.
Auxiliary Information— Staff Liaison:Behnam Davani,Ph.D.,MBA,Senior Scientist
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 1384
Phone Number:1-301-816-8394