Evaluation of a Novel Fluorosurfactant for Beclomethasone Dipropionate Pressurized Inhaler with HFA 134a as the Choice Propellant

Abstract

The in-vitro performance of a novel fluorosurfactant was evaluated for a formulation of beclomethasone dipropionate pressurised inhaler with propellant HFA 134a. The fluorosurfactant is a non-ionic polymeric fluorinated alkly ester.
Formulations were prepared by adding 0.05g of beclomethasone dipropionate and between 0.001-0.20g of the fluorosurfactant into polyethylene clear plastic canisters, followed 'by 10m1 of the propellant. Particle size characteristization was then performed by the Malvern particle sizer. A Twin Stage Impinger, operated at 60m1 was used to study deposition characteristics. HPLC assay was used to determine the drug recovered from the impinger stages.
A significantly higher (P<0.05) particle fraction of 46.30%, calculated as the amount of drug collected from stage 2 expressed as a percentage of the total drug in the stage 1 and 2 of the TSI, was obtained from the batch with surfactant concentration of 0.1% w/v. This compared with 34.45% for a commercial chlorofluorocarbon beclomethasone inhaler product. However, the mass median diameters (MMD) in both cases, as determined by the Malvern sizer instrument were 3.50p.m.
The fluorosurfactant performs well as a dispersing agent for HFA beclomethasone inhaler as evidenced by the higher particle fraction. Optimization of the formulation should be done with propellant HFA 134a and 227. A solution system should also be explored.