Referencesolution(a), Dissolve.5 mg of bromhexine impurityC RS in methanol, add 1.0 m1 of the test solution and dilute to10.0 rnl withthe same solvent.Reference solution (b). Dilute 1.0 rnl of the test solution to100.0 rnl withmethanol.Dilute 1.0 rnl of thissolutionto 10.0 rnlwith the same solvent.Chromatographic system- a stainless steel column 12 cm x 4.6 mm, packed withendcapped octadecylsilane bonded to porous silica(3 !J1Il),- mobilephase: amixture of 20volumes of buffersolutionprepared by dissolving 0.5 rnl of orthophosphoric acidto 950.0 ml of water, adjust the pH to 7.0 withtriethylamine, dilute to 1000 rnl and 80 volumes ofacetonitrile,- flow rate. 1 rnl perminute,- spectrophotometer set at 248 urn,- injection volume. 10 Iii.The relative retention time with reference to bromhexinehydrocWoride for bromhexine hydrocWoride impurity A isabout 0.1, for bromhexine hydrocWoride impurity B is about0.2, forbromhexinehydrocWorideimpurity Cis about0.4andforbromhexinehydrocWoride impurityD is about0.5.