The method is based on the reduction of the antihypertensive drug
substances including an aromatic nitro group by boiling them with cadmium metal in 0.05 N HCl
medium under CO2 atmosphere for 1 h under reflux. The amounts of the drugs were calculated by
determining the atomic absorbances of the released Cd+2. The calibration graphs were plotted between
the absorbance Cd+2concentrations in the range of 0.242 to 1.209 µg.cm−3 for nimodipine. As a reference
method, the spectrophotometric procedure was developed. The 2 methods developed were applied to
the assay of nimodipine in commercial tablet formulations, and a statistical comparison of the results
with those obtained from the reference method showed good agreement. The method has the advantage
of being simple, inexpensive, and easy to perform.