Manipulating Mean Centering of Ratio and First Derivative of Ratio Spectra Methods for Simultaneous Determination of Formoterol Fumarate and Budesonide in Drug Substances and Combined Pressurized Metered Dose Inhaler

Abstract

Two smart and selective spectrophotometric methods namely mean centering of ratio spectra and first derivative of ratio spectra have been described and validated for simultaneous determination of Formoterol Fumarate and Budesonide in Pressurized Metered Dose Inhaler. Mean centering of ratio depends on using the mean centered ratio spectra and measuring the mean centered values of the ratio spectra at 266 nm for FOF and BUD. The derivative ratio spectra method is based on the measurement of analytical signals at 290, and 304 nm for FOF and at 262, and 270 nm for BUD in the first derivative of ratio spectra. Instrumental parameters and divisors concentration were carefully studied; moreover the methods have been validated as per ICH guidelines. Linearity of the two methods was obeyed in the concentration range 0.1–10 μg/mL for FOF and 3.6–36 μg/mL For BUD. Detection limit was found to be 0.058, 0.062 μg/mL for FOF and 0.33, 0.23 μg/mL of BUD for mean centering of ratio and first derivative of ratio spectra methods, respectively. The recommended procedures were successfully applied for the determination of FOF and BUD in Symbicort® turbuhaler and the results demonstrated that the suggested methods are reliable and suitable for routine use with short time analysis. The results were statistically analyzed and confirmed accuracy and precision.