Determination of hydrazine in pharmaceuticals III: hydralazine and isoniazid using GLC

A GLC procedure has been developed for the determination of hydrazine in hydralazine and isoniazid drug raw materials, single and multicomponent tablets, injectables, and syrups. The method is based on the derivatization of hydrazine with benzaldehyde to form benzalazine. The minimum detectable amount of hydrazine in hydralazine and isoniazid raw materials and formulations is approximately 0.0003%. No hydrazine was found in the hydralazine raw material specimens examined. Traces of hydrazine (approximately 0.0003%) were found in some tablet lots and approximately 0.02% was found in an injectable product. A trace of hydrazine was found in one lot of isoniazid raw material and low levels (0.0012 and 0.0029%) were found in isoniazid tablet products. An isoniazid syrup contained approximately 0.2% hydrazine.