1995 OPEN FORUM Abstracts
CHARACTERIZATION OF LIPOSOME-LADEN AEROSOLS DELIVERED BY A MULTIPORT AEROSOL CHAMBER
Janette M. Wagonseller, BS, CRTT, Diane Kachel, BS, and Douglas G. Perry, PhD, RRT
Respiratory Therapy Program, School of Allied Health Sciences, and Division of Pulmonary and Critical Care Medicine, Indiana University School of Medicine, Indianapolis IN 46202.
Introduction: Aerosolization of medication to the lungs is a common procedure in treating lung disease. However, aerosolization has been limited to delivery of water-soluble drugs. A new form of drug packaging has been developed: Liposomes are drug-containing artificial vesicles. Aerosolization of liposomes is emerging as a promising treatment strategy. To develop a mouse model to study aerosolized liposomes, we investigated the use of a specially designed multiport chamber to deliver aerosols to rodents. The purpose of this project was to characterize aerosols containing liposomes delivered by this multiport aerosol chamber.
Methods: Aerosols with and without liposomes were generated by ultrasonic nebulization and sampled either directly from the nebulizer or from a multiport aerosol chamber. Samples were gravimetrically analyzed for aerosol particle size and distribution using a cascade impactor.
Results: Mass median diameter (MMD) for standard aqueous aerosols from the nebulizer and from the chamber was 4.9 and 4.8 µm, respectively; MMD for liposomeladen aerosols from the nebulizer and chamber was 4.2 and 3.8 µm, respectively. For each of the experimental conditions, aerosol particle size distribution, quantified as geometric standard deviation (\sigma_g) was 1.60, 1.50, 1.35, and 1.60, respectively. Conclusion: The multiport aerosol chamber had little or no effect on particle size (MMD) with either standard aqueous aerosols or liposome-laden aerosols. In addition, the multiport chamber had no effect on the distributions of aerosol particle size. In contrast, addition of liposomes in the aerosol produced a modest decrease in particle size with virtually no effect on particle size distribution.