A spectrophotometric procedure is developed for the determination od orphenadrine citrate (I), tizanidine HCl (II) and pancuronium bromide (III). The method is based on ion pair complex formation with Mo(V) thiocyanate complex in an acidic medium. Dichloroethane is used for the extraction of the orange red ion pair and its absorbance is measured at 470 nm. The molar absorptivity and Sandell sensitivity are also calculated. Obedience to Beer`s law lies in the concentration range of 5 – 35 µg/ml. the proposed method is applied successfully for the analysis of samples in bulk powder and in dosage forms with recoveries in the range of 99.8 – 101.4%.
J. Drug Res. Egypt, 23, 259–262 (2000).