Nanocrystals and amorphous nanoparticles and method for production of the same by a low energy process

A process for the preparation of nanocrystals or amorphous nanoparticles of an active comprising:

• i) providing a macrosuspension comprising a dispersion of a micrometer-sized material comprising an active in a solution of a surfactant or a steric stabiliser, wherein the active is in the solid state and remains in the solid state during the process;
• ii) stirring the macrosuspension for at least 1 minute at a rotational speed above 500 rounds per minute (rpm) using a rotor-stator mixer;
• and
• iii) passing the macrosuspension through a jet stream or piston-gap type high pressure homogenizer to produce nanocrystals or amorphous nanoparticles of the active wherein the homogenization in step iii) takes place at a pressure below 1,500 bar applying up to 20 homogenization cycles maximum.