ABSTRACT
Two simple, rapid and accurate spectrophotometric and spectrofluorimetric methods developed for the determination of Tofisopam (TF) in pure form and in pharmaceutical formulation. The spectrophotometric method (A) is based on the reduction of ferric into ferrous in presence of 1, 10-phenanthroline to give an orange –red colored ferroin complex measured at 510 nm. Method (B) spectrofluorimetric method is based on the oxidative coupling reaction of TF with 3-methylbenzothiazolin-2-one hydrazone (MBTH) hydrochloride in presence of cerium (IV) ammonium sulfate in an acidic medium. The quenching effect of TF on the fluorescence of excess cerous ions is measured at the emission λem 345 nm with excitation λex at 296 nm. The factors affecting the reactions were carefully studied and optimized. Beer,s law is obeyed in the range of 2-12 μg ml-1 for both methods with the mean percentages recovery of 100.04 ± 0.445 and 99.29 ± 0.563 for method (A) and (B), respectively. The two proposed methods were successfully applied for the determination of TF in Nodeprine tablets. Statistical comparison between the results obtained by these methods and that obtained by the official method for the determination of the drug was done, and it was found that there was no significant differences between them.
ABSTRACT
Two simple, accurate and sensitive spectrophotometric methods were developed for the determination of ticlabendazole in bulk and pharmaceutical formulation. These methods were based on the formation of ion-pair association complex (1:1) with bromocresol purple (BCP) and bromophenol blue (BPB). The coloured products were extracted into chloroform and measured spectrophotometrically at 420 nm. Linearity ranges were 20 – 100 μg/ml for BCP and 10 – 100 μg/ml for BPB, the mean percentage recoveries were 99.61±1.152% and 99.60±0.986% for BCP and BPB respectively. Statistical comparison between the results obtained by these methods and the manufacturer’s method was done, and no significance difference was obtained.
ABSTRACT
Three simple and sensitive methods were developed for the determination of a mixture of Rabeprazole sodium RB and Domperidone DP without prior separation. The first method A, isoabsorptive point comprised of measurement the total content of the mixture at their isoabsorptive point, while the content of RB was determined by measuring the first order derivative of its spectra at 231 nm, and the content of DP could be calculated by subtraction. The second method, B was based on the mean centering of ratio spectra, the concentration of RB was determined by measuring the amplitude at 256.4 nm and the concentration of DP was determined by measuring the amplitude at 311.8 nm. The third method C, dual wavelength method, the wavelengths selected for determination of Rabeprazole were 270 nm & 301 nm, whereas, the wavelengths selected for determination of Domperidone were 260 and 297.2 nm. The percentages mean accuracy for RB were 99.74 ± 0.498 % for method (A), 100.52 ± 0.478 % for (B) and 100.43 ± 0.502 % for (C) respectively. And that of DP were 100.28 ± 0.488 % for method (A), 99.24 ± 0.551 % for (B) and 99.95 ± 0.516 % for (C) respectively. The obtained results were statistically compared with those obtained by the official methods, showing no significant difference with respect to accuracy and precision.