Patent ID: 9162160
Filing Date: 2015-10-20
Classification: A61P,B01D,B01J,C07J

Abstract:
1. A process for preparing crystalline particles of at least one active principal suitable for inhalation therapy in the presence of ultrasonic irradiation that comprises adding, in an ultrasonic flow cell forming part of a closed flow loop, a solution of at least one solute in a solvent in a first flowing stream into an anti-solvent in a second flowing stream causing the mixing and contacting thereof, wherein the flow rate ratio of the anti-solvent: solvent is higher than 20:1, the ultrasonic irradiation inducing nucleation and so crystallization of the at least one solute, and, during addition of the solution, recirculating the anti-solvent stream with the added solvent, with at least one solute and the resultant crystalline particles as a continuously recirculating stream around the closed flow loop and through the ultrasonic flow cell, wherein there is a pre-set volume of the anti-solvent in the closed flow loop, and the volume of the anti-solvent and the flow rate of the anti-solvent are selected such that, during the period of addition of the solution, the anti-solvent is recirculated multiple times around the closed flow loop, and subsequently collecting the crystalline particles that are generated.