Simultaneous Determination of Montelukast Sodium and Bambuterol Hydrochloride in Tablet Dosage Form by Ultraviolet Spectrophotometry (dual Wavelength Method)

1 Pioneer Pharmacy Degree College, Near Ajwa Cross Road, N.H. -8, Ajwa-Nimeta Road, At & Post Sayajipura, vadodara – 390019, Gujarat, India. 2 Department of Pharmaceutical Chemistry, S. K. Patel College of Pharmaceutical Education and Research, Ganpat University, Kherva, Mehsana 382711, Gujarat, India. ABSTRACT A simple, accurate, and precise dual wavelength spectrophotometric method was developed for simultaneous determination of Montelukast sodium (MTKT) and Bambuterol hydrochloride (BAM) in combined pharmaceutical dosage forms. The principle for dual wavelength method is “the absorbance difference between two points on the mixture spectra is directly proportional to the concentration of the component of interest”. The method based on determination of MTKT at 322.0 nm using its absorptivity value and BAM at 266.0 nm after deduction of absorbance due to MTKT. The two drugs follow Beer-Lambert’s law over the concentration range of 10-80 μg/mL for MTKT and 40-240 μg/mL for BAM. The % estimation of the drugs was found near to 100 % representing the accuracy of the three methods. The recovery of the MTKT and BAM were found near to 100 %. Validation of the proposed methods was carried out for its accuracy, precision, specificity and ruggedness according to ICH guidelines. The proposed methods can be successfully applied in routine work for the determination of MTKT and BAM in combined dosage form.