IMPROVEMENTS IN OR RELATING TO POWDERS

摘要

Particles of an amino acid such as leucine may be formed from an amino acid vapour, for example by aerosol condensation, or by spray drying. The amino acid particles have a bulk density of not more than 0.1 gcm<-3> or have a mass median aerodynamic diameter of not more than 10 mu m or are in the form of flakes having a thickness of not more than 100 mu m. The inclusion of the particles of amino acid in powder for use in dry powder inhalers has been found to improve the respirable fraction of the active material in the powder.