A: The retention times of the major peaks in the chromatogram of the Assay preparationcorrespond to those in the chromatogram of the Standard preparation,as obtained in the Assay.

B: Asolution of it responds to the test for Sulfate á191ñ.

C: Transfer a volume of Syrup,equivalent to about 6mg of brompheniramine maleate,to a separator,add 0.5mLof ammonium hydroxide and 5mLof methylene chloride,shake for 1minute,and allow the layers to separate.Use the clear,lower layer as the test solution.Prepare separate Standard solutions in methanol containing,respectively,1.2mg of USP Brompheniramine Maleate RSand 9mg of USP Pseudoephedrine Sulfate RSper mL.Separately apply 5µLof each solution to a suitable thin-layer chromatographic plate (see Chromatography á621ñ)coated with a 0.25-mm layer of chromatographic silica gel mixture.Allow the spots to dry,and develop the chromatogram in a solvent system consisting of a mixture of ethyl ether,methanol,and ammonium hydroxide (16:3:1)until the solvent front has moved about three-fourths of the length of the plate.Remove the plate from the developing chamber,mark the solvent front,and allow the solvent to evaporate.Locate the spots on the plate by examination under short-wavelength UVlight:the RFvalues of the two principal spots obtained from the test solution correspond to those obtained from the Standard solutions.

Add the following:

For Syrup Packaged In Single-Unit Containers: meets the requirements.USP28

Add the following:

For Syrup Packaged In Multiple-Unit Containers: meets the requirements.USP28

Mobile phase— Prepare a mixture of water,acetonitrile,methanol,and tetrahydrofuran (550:320:80:50).Transfer 1.0mLof phosphoric acid,followed by 4.33g of dodecyl sulfate sodium to this mixture,and mix.Adjust with ammonium hydroxide to a pHof 3.50±0.05,filter,and degas.Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).[NOTE—The pHof the Mobile phase is critical and may cause 1to 4minutes of differences in the retention times of internal standard and brompheniramine maleate.]

Internal standard solution— Transfer about 50mg of naphazoline hydrochloride to a 100-mLvolumetric flask,add Mobile phaseto volume,and mix.

Standard preparation— Dissolve an accurately weighed quantity of USP Brompheniramine Maleate RSin Mobile phase,and quantitatively dilute with Mobile phaseto obtain a solution having a known concentration of about 6000Jµg per mL,Jbeing the ratio of the labeled amount,in mg,of brompheniramine maleate to the labeled amount,in mg,of pseudoephedrine sulfate per mL(Solution P).Transfer about 30mg of USP Pseudoephedrine Sulfate RS,accurately weighed,to a 25-mLvolumetric flask,add 5.0mLeach of Solution Pand Internal standard solution,dilute with Mobile phaseto volume,and mix to obtain a Standard preparationhaving known concentrations of about 1200Jµg of USP Brompheniramine Maleate RSper mLand about 1.2mg of USP Pseudoephedrine Sulfate RSper mL.

Assay preparation— Using a “To contain”pipet transfer an accurately measured volume of Syrup,equivalent to about 30mg of pseudoephedrine sulfate,to a 25-mLvolumetric flask.Rinse the pipet with about 5mLof Mobile phase,collecting the rinse in the volumetric flask.Add 5.0mLof Internal standard solution,dilute with Mobile phaseto volume,and mix.

Chromatographic system(see Chromatography á621ñ)— The liquid chromatograph is equipped with a 254-nm detector and a 4-mm ×30-cm column that contains packing L11.The flow rate is about 1.5mLper minute.Chromatograph the Standard preparation,and record the peak responses as directed for Procedure:the relative retention times are about 1.0for pseudoephedrine sulfate,1.5for naphazoline hydrochloride,and 2.5for brompheniramine maleate;the resolution,R,between the pseudoephedrine sulfate and naphazoline hydrochloride peaks is not less than 3,and between the brompheniramine maleate and naphazoline hydrochloride peaks is not less than 3;and the relative standard deviation for replicate injections is not more than 2.0%.

Procedure— Separately inject equal volumes (about 10µL)of the Standard preparationand the Assay preparationinto the chromatograph,record the chromatograms,and measure the responses for the major peaks.Calculate the quantity,in mg,of brompheniramine maleate (C16H19BrN2·C4H4O4)in each mLof the Syrup taken by the formula: in which Cis the concentration,in mg per mL,of USP Brompheniramine Maleate RSin theStandard preparation;Vis the volume,in mL,of Syrup taken;and RUand RSare the peak response ratios obtained for brompheniramine maleate and naphazoline hydrochloride from the Assay preparationand theStandard preparation,respectively.Calculate the quantity,in mg,of pseudoephedrine sulfate (C10H15NO)2·H2SO4in each mLof the Syrup taken by the same formula,changing the terms to refer to pseudoephedrine sulfate.