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.
Assay
Diluting solvent,Mobile phase,Standard preparation,Resolution solution,andChromatographic system
Prepare as directed in the
Assayunder
Tetracycline Hydrochloride.
Assay preparation
Transfer an accurately measured volume of Ophthalmic Suspension,equivalent to about 50mg of tetracycline hydrochloride,with the aid of 30mLof cyclohexane to a 125-mLseparator,add 30mLof Diluting solvent,insert the stopper,and shake.Allow to separate,and collect the lower layer in a 100-mLvolumetric flask.Repeat the extraction with two additional 30-mLportions of Diluting solvent,combining the extracts in the 100-mLvolumetric flask.Add Diluting solventto volume,mix,and filter.
Procedure
Proceed as directed for
Procedurein the
Assayunder
Tetracycline Hydrochloride.Calculate the quantity,in mg per mL,of C
22H
24N
2O
8·HCl equivalent in the Ophthalmic Suspension taken by the formula:
(CP/10V)(rU/rS),
in which
Vis the volume,in mL,of Ophthalmic Suspension taken,and the other terms are as defined therein.