Quick simultaneous analysis of bambuterol and montelukast based on synchronous spectrofluorimetric technique

Sensitive, simple and green analytical methodology for simultaneous estimation of bambuterol and montelukast as a combined medication based on their native fluorescence character was developed. The method relies on synchronous spectrofluorimetry to solve the problem of the overlapping emission spectra of the studied drugs. Using second derivative synchronous spectra enabled the simultaneous quantitation of bambuterol and montelukast without interference. The peak amplitudes of the aqueous solutions at Δλ = 20 nm were estimated at 284 and 304 nm for bambuterol and at 374 and 384 nm for montelukast. A linear relationship was achieved over the concentration range of 0.2-1.00 µg ml^-1 for bambuterol and 0.4-2.00 µg ml^-1 for montelukast. All factors and parameters were carefully studied to obtain the highest sensitivity and good precision of the proposed method. Additionally, the validation criteria were assessed in accordance with International Council of Harmonization (ICH) guidelines. The method was used for the estimation of both drugs in their raw materials, synthetic mixtures as well their combined tablets with good agreement between its results and those from the comparison method.