Identification—
The chromatogram of the
Assay preparationobtained as directed in the
Assayexhibits a major peak for tetracycline,the retention time of which corresponds to that exhibited in the chromatogram of the
Standard preparationobtained as directed in the
Assay.
Limit of 4-epianhydrotetracycline—
Using the
Diluting solvent,
Chromatographic system,and
Procedureset forth in the
Assay,chromatograph a Standard solution prepared by dissolving an accurately weighed quantity of
USP4-Epianhydrotetracycline Hydrochloride RSin
Diluting solventto obtain a solution having a known concentration of about 10µg per mL.Using the chromatogram so obtained and the chromatogram of the
Assay preparationobtained as directed in the
Assay,calculate the percentage of 4-epianhydrotetracycline in the Oral Suspension taken by the formula:
(25CE/T)(rU/rS),
in which
CEis the concentration,in µg per mL,of
USP4-Epianhydrotetracycline Hydrochloride RSin the Standard solution,
Tis the quantity,in mg,of tetracycline hydrochloride equivalent in the portion of Oral Suspension taken,based on the labeled quantity,and
rUand
rSare the 4-epianhydrotetracycline peak responses obtained from the
Assay preparationand the Standard solution,respectively:not more than 5.0%is found.
Assay—
Diluting solvent,Mobile phase,Standard preparation,Resolution solution,and Chromatographic system—
Prepare as directed in the
Assayunder
Tetracycline Hydrochloride.
Assay preparation—
Transfer an accurately measured volume of Oral Suspension,equivalent to about 125mg of tetracycline hydrochloride,to a 250-mLvolumetric flask,add 200mLof Diluting solvent,and shake.Add Diluting solventto volume,mix,and filter.
Procedure—
Proceed as directed in the
Assayunder
Tetracycline Hydrochloride.Calculate the quantity,in mg per mL,of C
22H
24N
2O
8·HCl equivalent in the Oral Suspension taken by the formula:
(CP/4V)(rU/rS),
in which
Vis the volume,in mL,of Oral Suspension taken,and the other terms are as defined therein.