Methods and apparatus are provided for making particles comprising: (a) spraying
an emulsion, solution, or suspension, which comprises a solvent and a bulk material
(e.g., a pharmaceutical agent), through an atomizer and into a primary drying chamber,
having a drying gas flowing therethrough, to form droplets comprising the solvent
and bulk material dispersed in the drying gas; (b) evaporating, in the primary
drying chamber, at least a portion of the solvent into the drying gas to solidify
the droplets and form particles dispersed in drying gas; and (c) flowing the particles
and at least a portion of the drying gas through a jet mill to deagglomerate or
grind the particles. By coupling spray drying with "in-line" jet milling, a single
step process is created from two separate unit operations, and an additional collection
step is advantageously eliminated. The one-step, in-line process has further advantages
in time and cost of processing.
