Micellar liquid chromatographic determination of five antianginals in pharmaceuticals

A procedure was developed for the determination of five antianginals (diltiazem, nadolol, nifedipine, propranolol and verapamil), using hybrid micellar mobile phases of sodium dodecyl sulphate (SDS) and pentanol, a C18 column and UV detection. All possible combinations of antianginals were resolved and determined using a mobile phase of 0.05 M SDS-5% pentanol with an analysis time of 9 min. Repeatabilities and intermediate precision were evaluated at four different drug concentrations in the 2-20 microg/ml (n=5) range. Limits of detection were in the range 0.028 microg/ml for diltiazem and 0.130 microg/ml for verapamil. The range of the limit of quantitation was from 0.092 to 0.431 microg/ml for the same compounds. Antianginal drugs were studied in pharmaceuticals with no interference from related compounds. The results of the analyses of pharmaceuticals formulations were in agreement with the declared compositions.