The Spray Drying of Unfractionated Heparin: Optimization of the Operating Parameters

Abstract

Unfractionated heparin is an anti-inflammatory mucoactive agent, with the potential to treat the inflamed and mucus-obstructed airways in patients with cystic fibrosis. In this study, unfractionated heparin has been spray-dried to produce spherical micronized particles in the size range 1–5 μm, which is suitable for delivery by dry-powder inhalation. Spray drying parameters have been optimized using a 2⁴ factorial experimental design. The feed concentration and atomization spray flow rate have the greatest effects on recovery (typically 60%) and particle size.

Keywords:

• spray drying
• factorial experimental design
• unfractionated heparin
• pulmonary drug delivery
• cystic fibrosis
• dry-powder inhaler

ACKNOWLEDGMENTS

We thank John Booth (Scientific and Medical Products Ltd, Cheadle, Manchester) for use of DVS equipment and Paul Gabbot and Paul Clarke (PETA Solutions, Oxford) for use of thermal analysis facilities. Jagdeep Shur is grateful to the Institute of Biomedical and Biomolecular Science (IBBS), University of Portsmouth, for providing a studentship.