Research Information System
Fabad Journal of Pharmaceutical Sciences, vol.25, no.3, pp.91-95, 2000 (Scopus)
Binary combinations of paracetamol (P) and mefenamic acid (M) were determined by pH induced difference spectrophotometry. For this purpose two sets of solutions of the compounds in 0.02 N methanolic NaOH and 0.02 N methanolic HCl were prepared. Acidic solutions were used as blank in the measurements. Difference absorbances of standard and sample solutions were read at 272.5 nm for P and 362.0 nm for M. The recoveries of P and M from standard mixture were 98.3% for P and 98.9% for M, respectively. Assay results of the commercial formulation were in good agreement with the stated contents of dosage units and with the results of Vierondt's method. The reproducibility of the assay result as relative standard deviation is 0.79% for P and 1.19% for M, respectively.