Related Experiment Video
Updated: Aug 13, 2026

A System to Create Stable Nanoparticle Aerosols from Nanopowders
Published on: July 26, 2016
A comparison of two methods to determine the solubility of compounds in aerosol propellants
Abhishek Gupta1, Paul B Myrdal
1Inhalation Formulation, Cardinal Health, P.O. Box 13341, Research Triangle Park, NC 27709, USA.
Abstract:
A new on-line reverse phase HPLC method for determining the solubility of compounds in propellant based metered dose inhaler (MDI) formulations was compared with a conventional method. The new method employs a direct injection from a MDI vial into the needle injector port of a manual injector. To evaluate the two methods, beclomethasone dipropionate (BDP), 5,5-diphenyl hydantoin and 3,3'-diindolylmethane, were used as model compounds in propellant HFA-134a. Comparison was performed by analyzing known and unknown concentrations of BDP in various combinations of HFA-134a and ethanol. In addition, the solubility of 5,5-diphenyl hydantoin and 3,3'-diindolylmethane were determined in HFA-134a using both the new and the conventional methods. The two methods were found to be in good agreement with each other, with the new direct injection technique offering enhanced precision and accuracy along with considerable reduction in analysis time.
Related Concept Videos
Molecular Comparison of Gases, Liquids, and Solids
Physical Properties Affecting Solubility
As for any solution, the solubility of a gas in a liquid is affected by the attractive intermolecular forces between solute and solvent species. Unlike solid and liquid solutes, however, there is no solute-solute intermolecular attraction to overcome when a gaseous solute dissolves in a liquid solvent since the atoms or molecules comprising a gas are far separated and experience negligible interactions. Consequently, solute-solvent interactions are the sole...
Vapor Pressure Lowering
Intermolecular Forces and Physical Properties
Atomic Absorption Spectroscopy: Atomization Methods
Gas Solubility

