Simultaneous Determination of Salmeterol Xinafoate and Fluticasone Propionate in Bulk Powder and Seritide Diskus using High Performance Liquid Chromatographic and Spectrophotometric Method

Abstract

Simultaneous Determination of Salmeterol xinafoate and Fluticasone propionate in bulk powder and Seritide® Diskus Using High Performance Liquid Chromatographic and Spectrophotometric Methods Abstract Five methods were developed for simultaneous determination of Salmeterol xinafoate and Fluticasone propionate without previous separation. In the first method (HPLC), a reversed-phase column and a mobile phase of acetonitrile:methanol (80:20 v/v) at 0.5 mL min-1 flow rate was used to separate both drugs and UV detection at 220 nm. Linearity was obtained in concentration ranges of 50-500 µg mL-1 for Salmeterol xinafoate and 50-500 µg mL-1 for Fluticasone propionate. In the second method both drugs were determined using first derivative UV spectrophotometry, with zero crossing measurement at 352 and 269.5 nm for Salmeterol xinafoate and Fluticasone propionate, respectively. The third method depends on first derivative of the ratios spectra by measurements of the amplitudes at 334 and 337.5 nm for Salmeterol xinafoate and 225 and 231.5 nm for Fluticasone propionate. Calibration graphs were established in the range of 4-28 µg mL-1 for both Salmeterol xinafoate and Fluticasone propionate. The fourth one depend on isosbestic point 237.5 nm, while the content of Salmeterol xinafoate was determined by measuring the absolute value of the ultraviolet curves at 343 nm, without interference from Fluticasone propionate. The fifth method depends on new calculations using the absorbance at 225 and 256.5 nm where the absorpativity of Salmeterol xinafoate is double the absorpativity of Fluticasone propionate, while the content of Salmeterol xinafoate was determined by measuring the absolute value of the ultraviolet curves at 343 nm, without interference from Fluticasone propionate. All the proposed methods were extensively validated. They have the advantage of being economic and time saving. All the described methods can be readily utilized for the analysis of pharmaceutical formulations. The results obtained by adopting the proposed methods were statistically analyzed and compared with those obtained by official methods.