6-Methyl-2-pyridinecarboxyldehyde (MPA) reacts with isoniazid to form hydrazone derivative. The concentration of MPA pH and warming time for the determination of isoniazid were optimized The absorbance was measured at 328 nm against reagent blank Beer's law was obeyed in the range of 1.46.8 mu g/mL isoniazid The method was used for the determination of isoniazid contents in pharmaceutical preparations individually and in the presence of ethambutol and rifampicin. The results were obtained with coefficient of variation (C.V) within 0.7-3.8%. 


M Y KHUHAWAR ,K F ALMANI ,K F ALMANI ,F M A RIND ,K F ALMANI ,F M A RIND ,F M A RIND ,