A: Infrared Absorption á197Mñ—

B: Ultraviolet Absorption á197Uñ—

C: The residue obtained by igniting it meets the requirements of the tests for Sodium á191ñ.

Test solution: 50mg per mL,in methanol.

Diluent,Mobile phase,andSystem suitability preparation— Proceed as directed in the Assay.

Standard solution— UseStandard flurbiprofen related compound Apreparation,prepared as directed in the Assay.

Test solution— Use theAssay preparation.

Chromatographic system— Proceed as directed in theAssay,except to chromatograph theStandard solutioninstead of theStandard preparation.

Procedure— Separately inject equal volumes (about 20µL)of theStandard solutionand theTest solutioninto the chromatograph,record the chromatograms,and measure the areas for the major peaks.Calculate the percentage of flurbiprofen related compound Ain the portion of Flurbiprofen Sodium taken by the formula: in which Cis the concentration,in µg per mL,ofUSP Flurbiprofen Related Compound A RSin the Standard solution;Wis the weight,in mg,of the portion of Flurbiprofen Sodium taken to prepare theTest solution;andrUandrSare the peak areas for flurbiprofen related compound Aobtained from theTest solutionand theStandard solution,respectively:not more than 1.5%is found.

Diluent— Mix 500mLof methanol and 250mLof water.

Mobile phase— Prepare a filtered and degassed mixture of acetonitrile,water,and glacial acetic acid (50:49:1).Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).

Standard flurbiprofen related compound Apreparation— Dissolve an accurately weighed quantity ofUSP Flurbiprofen Related Compound A RSin methanol to obtain a stock solution having a known concentration of about 150µg per mL.Transfer 1.0mLof this solution to a 200-mLvolumetric flask,dilute withDiluentto volume,and mix.

Standard preparation— Dissolve an accurately weighed quantity ofUSP Flurbiprofen RSin methanol to obtain a stock solution having a known concentration of about 1mg per mL.Transfer 5.0mLof this solution to a 100-mLvolumetric flask,dilute withDiluentto volume,and mix.

System suitability preparation— Transfer 5mLof the stock solution used to prepare theStandard preparationand 2mLof the stock solution used to prepare theStandard flurbiprofen related compound Apreparationto a 100-mLvolumetric flask,dilute withDiluentto volume,and mix.

Assay preparation— Transfer about 100mg of Flurbiprofen Sodium,accurately weighed,to a 100-mLvolumetric flask,dissolve in and dilute with methanol to volume,and mix.Transfer 5.0mLof this solution to a second 100-mLvolumetric flask,dilute withDiluentto volume,and mix.

Chromatographic system(seeChromatography á621ñ)— The liquid chromatograph is equipped with a 254-nm detector and a 4.0-mm ×25-cm column that contains 10-µm packing L7.The flow rate is about 2mLper minute.Chromatograph the System suitability preparation,and record the peak responses as directed for Procedure:the resolution,R,between flurbiprofen related compound Aand flurbiprofen is not less than 1.0.Chromatograph theStandard preparation,and record the peak responses as directed for Procedure:the tailing factor is not more than 2.5;and the relative standard deviation for replicate injections is not more than 1.0%.

Procedure— Separately inject equal volumes (about 20µL)of theStandard preparationand theAssay preparationinto the chromatograph,record the chromatograms,and measure the areas for the major peaks.Calculate the percentage of C15H12FNaO2·2H2Oin the portion of Flurbiprofen Sodium taken by the formula: in which 302.27and 244.27are the molecular weights of flurbiprofen sodium dihydrate and anhydrous flurbiprofen,respectively;Cis the concentration,in µg per mL,ofUSP Flurbiprofen RSin the Standard preparation;Wis the weight,in mg,of the portion of Flurbiprofen Sodium taken to prepare the Assay preparation;and rUand rSare the flurbiprofen peak responses obtained from theAssay preparationand theStandard preparation,respectively.