Nesrin K. Ramadan, Lamia M. Abd El Halim, Hoda F. A. EL Sanabary, Maissa Y. Salem
Two precise, accurate and sensitive UV-Spectrophotometric methods were developed and validated for the determination of Tiemonium methylsulphate in presence of its degradation product, first derivative spectrophotometric method (1D) and first derivative of ratio spectrophotometry (1DD). Forced degradation study was performed using 2N H2SO4 on cold. For the first method; upon examining the first derivative spectra of the drug and its degradation product, it was noticed that Tiemonium methylsulphate can be determined at 250 nm with zero contribution of its degradation product. The linearity range was 5.0 to 60.0 μg/mL. The mean percentage recovery was 100.17±0.622%. For the second method, zero order spectra of the drug were divided by the spectrum of 40 μg/mL of the degradation product as a divisor then the first order of the ratio spectra was obtained using = 8 and scaling factor 10. The peak amplitudes of the first derivative of the ratio spectra were measured at 250 nm. The linearity range was 5.0 to 60.0 μg/mL and the mean percentage recovery was 100.51±0.982%. Statistical comparison between the results obtained by these methods and those obtained by the manufacturer's method was done, and no significance difference was obtained
