A:Infrared Absorption á197Kñ.

B: The retention time of the major peak in the chromatogram of the Test solutioncorresponds to that in the chromatogram of the Standard solution,as obtained in the test for Related compounds.

0.01M Sodium 1-octanesulfonate solution— Dissolve 1.0814g of 1-sodium octanesulfonate in 500mLof water.

Mobile phase— Prepare a mixture of 0.01M Sodium 1-octanesulfonate solution,acetonitrile,glacial acetic acid,and triethylamine (81:19:2:0.5).Make adjustments if necessary (see System Suitabilityunder Chromatography á621ñ).

Standard solution— Dissolve an accurately weighed quantity of USP Bretylium Tosylate RSin Mobile phase,and dilute quantitatively,and stepwise if necessary,to obtain a solution having a known concentration of about 20µg per mL.

Test solution— Transfer about 200mg of Bretylium Tosylate,accurately weighed,to a 100-mLvolumetric flask,dissolve in and dilute with Mobile phaseto volume,and mix.

Chromatographic system(see Chromatography á621ñ)— The liquid chromatograph is equipped with a 265-nm detector and a 4.6-mm ×25-cm column that contains packing L11.The flow rate is about 1.9mLper minute.Chromatograph the Standard solution,record the chromatograms,and record the peak responses as directed for Procedure:the relative standard deviation for replicate injections is not more than 3.0%.

Procedure— Separately inject equal volumes (about 30µL)of the Test solutionand the Standard solutioninto the chromatograph,record the chromatograms,and measure the peak responses.The relative retention times are about 0.25,0.74,1.0,1.27,1.40for tosylate ion,o-bromobenzyldimethylamine,bretylium,m-bromobenzyldimethylamine,and p-bromobenzyldimethylamine,respectively.The sum of the responses for all the peaks,excluding those of the bretylium and tosylate peaks,from the Test solutionis not more than two times the bretylium response from the Standard solution(2%);and no individual peak response is greater than that of the bretylium peak from the Standard solution(1%).