for solution packaged in single-unit containers: meets the requirements.

Mobile phase , Standard preparation, and Chromatographic system—Proceed as directed in the Assay under Clindamycin Hydrochloride.

Assay preparation— Transfer an accurately measured volume of Oral Solution, equivalent to about 85 mg of clindamycin, to a 100-mL volumetric flask, dilute with Mobile phase to volume, and mix.

Procedure— Separately inject equal volumes (about 10 µL) of the Standard preparation and the Assay preparation into the chromatograph, record the chromatograms, and measure the areas for the major peaks. Calculate the quantity, in mg, of clindamycin (C18H33ClN2O5S) in each mL of the Oral Solution taken by the formula: in which C is the concentration, in mg per mL, of USP Clindamycin Hydrochloride RS in the Standard preparation; P is the potency, in µg of clindamycin per mg, of USP Clindamycin Hydrochloride RS; V is the volume, in mL, of Oral Solution taken to prepare the Assay preparation; and rU and rS are the clindamycin peak area responses obtained from the Assay preparation and the Standard preparation, respectively.