title: High-performance liquid chromatographic determination of isoniazid and 1-isonicotinyl-2-lactosylhydrazine in isoniazid tablet formulations.
abstract: A high-performance liquid chromatographic procedure is presented for the simultaneous determination of isoniazid and 1-isonicotinyl-2-lactosylhydrazine (I) in isoniazid tablet formulations. An aliquot of a diluted aqueous tablet extract is introduced onto a microparticulate cyanopropyl bonded-phase column using a valve-loop injector and chromatographed using a mobile phase of acetonitrile--0.01 M, pH 3.5 aqueous acetate buffer (5:95). Compound I can be determined at levels as low as 0.5% of the isoniazid label claim. The relative standard deviations are 0.4 and 0.7% for the simultaneous determination of isoniazid and I, respectively. Seven commercial tablet formulations contained 93.8--97.0% of the labeled isoniazid amounts and 0.3--5.8% of I, expressed as equivalent isoniazid relative to the labeled isoniazid level.
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004355:Drug Stability; D007538:Isoniazid / Q000031:analogs & derivatives* / Q000032:analysis*; D007785:Lactose / Q000031:analogs & derivatives* / Q000032:analysis; D008722:Methods; D013607:Tablets
chemical_list: D013607:Tablets; C023657:1-isonicotinyl-2-lactosylhydrazine; D007785:Lactose; D007538:Isoniazid