University of Worcester Worcester Research and Publications

Enhanced Dispersibility and Deposition of Spray-dried Powders for Pulmonary Gene Therapy

Li, H.-Y., Neill, H., Innocent, R., Seville, Peter C. ORCID:, Williamson, I. and Birchall, J.C. (2003) Enhanced Dispersibility and Deposition of Spray-dried Powders for Pulmonary Gene Therapy. Journal of Drug Targeting, 11 (7). pp. 425-432. ISSN Print: 1061-186X Online: 1029-2330

Full text not available from this repository. (Request a copy)


Spray-drying represents a viable alternative to freeze-drying for preparing dry powder dispersions for delivering macromolecules to the lung. The dispersibility of spray-dried powders is limited however, and needs to be enhanced to improve lung deposition and subsequent biological activity. In this study, we investigate the utility of leucine as a dry powder dispersibility enhancer when added prior to spray-drying a model non-viral gene therapy formulation (lipid:polycation:pDNA, LPD). Freeze-dried lactose–LPD, spray-dried lactose–LPD and spray-dried leucine–lactose–LPD powders were prepared. Scanning electron microscopy showed that leucine increased the surface roughness of spray-dried lactose particles. Particle size analysis revealed that leucine-containing spray-dried powders were unimodally dispersed with a mean particle diameter of 3.12 μm. Both gel electrophoresis and in vitro cell (A549) transfection showed that leucine may compromise the integrity and biological functionality of the gene therapy vector. The deposition of the leucine containing powder was however significantly enhanced as evidenced by an increase in gene expression mediated by dry powder collected at lower stages of a multistage liquid impinger (MSLI). Further studies are required to determine the potential of leucine as a ubiquitous dispersibility enhancer for a variety of pulmonary formulations.

Item Type: Article
Additional Information:

The full-text cannot be supplied for this item. Please check availability with your local library or Interlibrary Requests Service.

Uncontrolled Discrete Keywords: leucine, LPD complex, non-viral gene therapy, pulmonary deposition, spray-drying
Divisions: College of Health, Life and Environmental Sciences > School of Science and the Environment
Related URLs:
Depositing User: Peter Seville
Date Deposited: 17 Jun 2019 09:42
Last Modified: 17 Jun 2020 17:30

Actions (login required)

View Item View Item
Worcester Research and Publications is powered by EPrints 3 which is developed by the School of Electronics and Computer Science at the University of Southampton. More information and software credits.