| Abstract: | Derivative ratio spectrophotometric and differential derivative spectrophotometric methods, for the determination of isoniazid and pyridoxine hydrochloride in pharmaceutical dosage forms (tablets) is described. The first method depends on ratio derivative spectra spectrophotometry where isoniazid and pyridoxine hydrochloride were determined by the measurement of the first derivative ratio spectra of amplitudes (Abs.) at 250.7 and 305.8 nm, respectively. The other method, is based on differential derivative spectrophotometry for the simultaneous determination of isoniazid and pyridoxine hydrochloride in binary mixture without any pre-treatment by measuring the ΔD1 values. Both methods showed good linearity, precision and reproducibility. The proposed methods were successfully applied to the pharmaceutical dosage forms containing the above-mentioned drug combination without any interference by the excipients. |
