Metronidazole Benzoate
;)
2-(2-Methyl-5-nitroimidazol-1-yl)ethyl benzoate [13182-89-3].
»Metronidazole Benzoate contains not less than 98.5percent and not more than 101.0percent of C13H13N3O4,calculated on the dried basis.
Packaging and storage—
Preserve in well-closed,light-resistant containers.Store at 25
,excursions permitted between 15and 30.
,excursions permitted between 15and 30.
Identification—
B:
The principal spot in the chromatogram of the Test solutioncorresponds to that in the chromatogram of Standard solution A,as obtained in the test for Related compounds.
Acidity—
Neutralize 40mLof a mixture of dimethylformamide and water (1:1)with hydrochloric acid or 0.02Msodium hydroxide,add 0.2mLof methyl red TSand 2.0g of Metronidazole Benzoate,mix to dissolve,and titrate with 0.02Msodium hydroxide:not more than 0.25mLis required to produce a color change.
Loss on drying á731ñ—
Dry it at 80for 3hours:it loses not more than 0.5%of its weight.
for 3hours:it loses not more than 0.5%of its weight.
Residue on ignition á281ñ:
not more than 0.1%.
Heavy metals,Method IIá231ñ:
0.002%.
Related compounds—
Adsorbent:
0.2-mm layer of chromatographic silica gel mixture.
Test solution—
Transfer about 200mg of Metronidazole Benzoate,accurately weighed,to a 10-mLvolumetric flask,dissolve in and dilute with acetone to volume,and mix.
Standard solution A—
Dissolve an accurately weighed quantity of USP Metronidazole Benzoate RSin acetone,and dilute quantitatively,and stepwise if necessary,with acetone to obtain a solution having a known concentration of about 0.1mg per mL.
Standard solution B—
Transfer 4.0mLof Standard solution Ato a 10-mLvolumetric flask,dilute with acetone to volume,and mix.
Standard solution C—
Transfer about 10mg each of metronidazole and 2-methyl-5-nitroimidazole,accurately weighed,to a 50-mLvolumetric flask,dissolve in and dilute with acetone to volume,and mix.
Application volume:
10µL.
Developing solvent system:
ethyl acetate.
Procedure—
Proceed as directed for Thin-Layer Chromatographyunder Chromatography á621ñ.Examine the plate under short-wavelength UVlight:the test is valid only if the metronidazole and 2-methyl-5-nitroimidazole spots obtained from Standard solution Care clearly separated;no spot obtained from the Test solutionis larger or more intense than the principal spot obtained from Standard solution A(0.5%);and not more than three spots,excluding the principal spot,obtained from the Test solutionare larger or more intense than the principal spot obtained from Standard solution B(1.0%).
Organic volatile impurities,Method IVá467ñ:
meets the requirements.
Assay—
Transfer about 250mg of Metronidazole Benzoate,accurately weighed,to a suitable container,and dissolve with stirring in 50.0mLof glacial acetic acid.Titrate with 0.1Nperchloric acid,determining the endpoint potentiometrically.Perform a blank determination,and make any necessary correction (see Titrimetry á541ñ).Each mLof 0.1Nperchloric acid is equivalent to 27.53mg of C13H13N3O4.
Auxiliary Information—
Staff Liaison:Behnam Davani,Ph.D.,MBA,Senior Scientist
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 1286
Pharmacopeial Forum:Volume No.29(5)Page 1537
Phone Number:1-301-816-8394