Two simple, accurate and sensitive methods for determination of flurbiprofen (FLUR) in pure and dosage forms had
been developed and validated. The first method is based on the formation of ion-associate complexes between the
drug and arsenazo I (ARS I) or Bromophenol blue (BPB) to give colored products maximally absorbed at 556 and
635 nm with the two reagents, respectively. The optimum conditions that favor the formation of the ion pair
complexes were extensively studied and optimized. Beer's law was obeyed up to 90.20 and 100.85 µgmL-1 while
Ringboom concentration ranges are 1.89 - 89.20 and 2.00 – 96.60 µgmL-1 for the two reagents, respectively. In the
second method, first derivative (1DD) spectrophotometry was used for the determination where it was found that
FLUR exhibits maximum amplitude at 259 nm. At this wavelength, linear relation between concentration and
absorbance was obtained with high correlation coefficients. The methods were validated, in terms of accuracy and
precision and the results are satisfactory. The proposed methods were successfully applied for determination of
FLUR in pure and pharmaceutical dosage form without interference from the common excipients. The results
obtained by the proposed methods were comparable with those obtained by reference methods.