Packaging and storage
Preserve in single-dose,light-resistant containers,preferably of Type Iglass.
Limit of cephaeline
[NOTEConduct this test in subdued light until after the chromatogram has been completely developed.
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Test preparation
Evaporate 1.0mLof Injection on a steam bath with the aid of a stream of nitrogen just to dryness.Dissolve the residue in a sufficient volume of methanol to obtain a Test preparationhaving a concentration of 10mg of emetine hydrochloride per mL.
Assay
Transfer an accurately measured volume of Injection,equivalent to about 120mg of emetine hydrochloride,to a suitable extraction apparatus containing about 20mLof water.Add 6Nammonium hydroxide until the solution is strongly alkaline,and extract with ether until 0.5mLof the water layer,slightly acidified with hydrochloric acid,remains unaffected by the addition of a few drops of mercuric-potassium iodide TS.Evaporate the combined ether extracts on a steam bath,allowing the last few mLof the ether to evaporate spontaneously.Add to the residue 2mLof neutralized alcohol and 30.0mLof 0.02Nsulfuric acid VS,and warm gently until the alkaloid is dissolved.Cool,add methyl red TS,and titrate the excess acid with 0.02Nsodium hydroxide VS.Each mLof 0.02Nsulfuric acid is equivalent to 5.536mg of C29H40N2O4·2HCl.