A simple and economic chromatographic method for simultaneous determination of six bronchodilator drugs in pharmaceutical dosage forms

Abstract

Chronic obstructive pulmonary disease is a major cause of morbidity and mortality worldwide. Combining an inhaled anticholinergic and a β2-agonist are a convenient way of delivering treatment, obtaining better lung function and improved symptoms. We aimed to develop and validate a reliable HPLC method for the simultaneous determination of the anticholinergics; ipratropium bromide, glycopyrronium bromide and tiotropium bromide in addition to the β2-agonists; bambuterol hydrochloride, formoterol fumarate and indacaterol maleate. The chromatographic separation was achieved on a Phenomenex Luna phenyl-hexyl (250 × 4.6 mm i.d., 5 μm) column and a mobile phase composed of 0.2% phosphoric acid (pH 3.0)/methanol/acetonitrile (66:12:22, v/v/v). The analysis was performed at a flow rate of 1 mL/min with UV detection at 210 nm. Method validation showed that calibration curves were linear within the range from 0.5 to 30.0 μg/mL with a correlation coefficient > 0.998. Intraday and interday precision and accuracy evaluated by relative standard deviation were lower than 2%. The limits of detection were in the ranges of 0.037–0.152 μg/mL. The developed method which is rapid, sensitive and highly efficient was applied for the analysis of the six bronchodilators in single and combined formulations saving money, solvents and chemicals. In addition, the environmental impact of the proposed method was evaluated using a suitable analytical Eco-Scale.