3.1 Ratio first derivative Spectrophotometric method
The ratio spectra of different AZH standards at increasing concentrations in methanol obtained by
dividing each with the stored zero order spectrum of standard solution of FLU (12 ug/ml) are shown
in Figure 2(b) and the first derivative of these spectra traced with the interval of ??= 2 nm are
illustrated in Figure 2(c).found as optimum for the first derivative of their ratio spectra was 2 nm. From the Figure 2(c), Figure 3(c), Figure 4(c) and Figure 5(C)
wavelength maxima 288.19 nm, 237.16 nm, 242.20 nm and 288.50 nm were selected for the
determination of the AZH, FLU, CLO and DES respectively in the assay of pharmaceutical preparation
due to its lower R.S.D. (relative standard deviation) value and more suitable mean recovery.Similarly, the ratio derivative
spectra of the solutions of CLO in different concentrations in methanol traced with the interval of ??=
2 nm by using the zero order spectra of DES (400 ug/ml) as divisor by computer aid is demonstrated
in Figure 4 and the ratio derivative spectra of the solutions of DES in different concentrations in
methanol recorded with the interval of ??= 2 nm by using the zero order spectra of CLO (6 ug/ml) as
divisor by computer aid is demonstrated in Figure 5.Similarly, the ratio derivative spectra of the solutions of FLU in different
concentrations in methanol traced with the interval of ??= 2 nm by using the zero order spectra of
AZH (15 ug/ml) as divisor by computer aid is demonstrated in Figure 3.The ??