An investigation into the morphology of loxapine in a thermal aerosolization process from crystalline to amorphous.

A highly pure aerosol of the antipsychotic drug, loxapine, can be thermally generated through vaporization from a thin coating of loxapine on a stainless steel substrate with the formation of a condensation aerosol. Because loxapine can exist in two polymorphic forms, the morphological time course from loxapine drug substance to coating on the substrate (intermediate product) and ultimately to the aerosol was investigated using differential scanning calorimetery, X-ray diffraction (XRD), Fourier transform infrared, and Raman spectroscopy. Monoclinic and orthorhombic crystalline forms of loxapine were confirmed by single crystal and powder XRD.