On-line high-performance liquid chromatography method for analyte quantitation from pressurized metered dose inhalers

Area of Science:

• Analytical Chemistry
• Pharmaceutical Analysis

Background:

• Traditional methods for analyzing metered dose inhaler (MDI) formulations require sample dilution, complicating analysis and potentially introducing errors.
• Quantitating low concentrations of active pharmaceutical ingredients in MDI systems presents analytical challenges due to formulation complexity.

Purpose of the Study:

• To develop a sensitive, rapid, on-line reversed-phase high-performance liquid chromatographic (HPLC) method for direct quantitation of compounds in pressurized MDI systems.
• To validate the developed HPLC method for accuracy, precision, sensitivity, and specificity using a model compound.

Main Methods:

• Developed an on-line HPLC method involving direct injection from the MDI vial, bypassing traditional dilution steps.
• Utilized a reversed-phase Apollo C18 column with an acetonitrile-water mobile phase and UV detection at 240 nm.
• Validated the method using ethanol-1,1,1,2-tetrafluoroethane (134a)-based MDIs and Beclomethasone dipropionate (BDP) as a model compound.

Main Results:

• The on-line HPLC method demonstrated high sensitivity and precision for quantitating low concentrations of compounds in MDI systems.
• Direct injection eliminated the need for sample dilution, simplifying the analytical procedure.
• The method provided accurate and specific results, with a retention time of 2.7 min for BDP.

Conclusions:

• The developed on-line HPLC method is a significant advancement for the rapid and accurate analysis of MDI formulations.
• This technique enhances analytical efficiency and reliability, particularly for low-concentration compounds.
• The method is suitable for quality control and research applications involving MDI products.