Chloramphenicol Cream
»Chloramphenicol Cream contains not less than 90.0percent and not more than 130.0percent of the labeled amount of C11H12Cl2N2O5.
Packaging and storage— Preserve in collapsible tubes or in tight containers.
Identification— The retention time of the major peak in the chromatogram of the Assay preparationcorresponds to that in the chromatogram of the Standard preparationas obtained in the Assay.
Minimum fill á755ñ: meets the requirements.
Assay—
Mobile phase and Chromatographic system—Proceed as directed in the Assayunder Chloramphenicol.
Standard preparation— Transfer about 40mg of USP Chloramphenicol RS,accurately weighed,to a 100-mLvolumetric flask,dissolve in methanol,dilute with methanol to volume,and mix.Transfer 10.0mLof the resulting solution to a 50-mLvolumetric flask,dilute with Mobile phaseto volume,and mix.Filter a portion of this solution through a 0.5-µm or finer porosity filter,and use the clear filtrate as the Standard preparation.
Assay preparation— Transfer an accurately weighed quantity of Chloramphenicol Cream,equivalent to about 40mg of chloramphenicol,to a 100-mLvolumetric flask,add about 80mLof methanol,and sonicate for about 10minutes.Cool to room temperature,dilute with methanol to volume,and mix.Transfer 10.0mLof the resulting solution to a 50-mLvolumetric flask,dilute with Mobile phaseto volume,and mix.Filter a portion of this solution through a 0.5-µm or finer porosity filter,and use the clear filtrate as the Assay preparation.
Procedure— Proceed as directed for Procedurein the Assayunder Chloramphenicol.Calculate the quantity,in mg,of C11H12Cl2N2O5in the portion of Cream taken by the formula:
0.5C(rU/rS),
in which the terms are as defined therein.
Auxiliary Information— Staff Liaison:William W.Wright,Ph.D.,Scientific Fellow
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 428
Phone Number:1-301-816-8335