Abstract

A sensitive and rapid high performance liquid chromatography method was developed and validated for the determination of aerodynamic characteristics of the emitted dose of budesonide from different inhaler dosage forms. The mobile phase consisted of a mixture of acetonitrile and 10 mM ammonium acetate (63:37% v/v) adjusted to pH5 with orthophosphoric acid. The HPLC analysis was performed at a flow rate of 1 mL/min using a C18 Zorbax Eclipse Plus column (250 x 4.6 mm, 5u) and an UV detection wavelength of 254 nm was used. The method was validated for specificity, linearity, precision, accuracy, limit of quantification, limit of detection, robustness and solution stability. The calibration curve was linear over a concentration range of 0.05 to 62.50 ug/mL (r² = 0.9999) with limit of detection and limit of quantification of 0.02 and 0.06 ug/mL, respectively. The intra-day and inter-day precision and accuracy were between 0.01 and 2.00% and -1.9 and 0.007%, respectively. The method was successfully applied to measure the amount of emitted and fine particle budesonide doses from Pulmicort Respules®, Pulmicort Inhaler® and Pulmicort Turbuhaler®.

Key words: Impactor, pulmicort, inhalation, HPLC, aerodynamic diameter, assay.