Author(s): Zijlstra GS, Brandsma CA, Harpe MF, Van Dam GM, Slebos DJ, Kerstjens HA, De Boer AH, Frijlink HW

Affiliation(s): Department of Pharmaceutical Technology and Biopharmacy, University of Groningen, Groningen, The Netherlands.

Publication date & source: 2007-11, Eur J Pharm Biopharm., 67(3):667-75. Epub 2007 Mar 31.

Publication type:

The purpose of this study was to formulate hemin as a powder for inhalation and to show proof of concept of heme oxygenase 1 (HO-1) expression in the lungs of mice by inhalation of hemin.

Hemin was spray dried from a neutralized sodium hydroxide solution. The particle size distribution of the powder was between 1 and 5 microm. Dispersion from the Twincer dry powder inhaler showed a fine particle fraction (<5 microm) of 36%. A specially designed aerosol box based on the Twincer-inhaler was used for a proof of concept study of HO-1 induction by inhalation of hemin in mice. The aerosol in the exposure chamber of the aerosol box remained aerosolized up to 5 min. A rhodamin B containing aerosol was used to show that the aerosol box gave deposition over the entire lung indicating the suitability of the model. Additionally, inhalation of hemin showed a dose dependent increase in HO-1 protein expression in the lungs.

In conclusion, hemin was successfully formulated as a powder for inhalation and the inhalation model allowed controlled HO-1 expression in the lungs of mice. Future studies investigating the utility of inhaled hemin in treating disease states are warranted.