Patent ID: 11964058
Assignee: EVONIK CORPORATION
Field: Pharmaceuticals (Chemistry)
Classification: CPC A  C | IPC A  C

Claim 0:
1. A process for preparing nanoparticles by emulsion-solvent extraction or emulsion-solvent evaporation and application of ultrasonic sound, the process comprising:
a) providing, in a first container, an organic phase (OP), comprising
a first solvent or solvent mixture S1, comprising one or more organic solvent(s), and
0.1 to 55% by weight of at least one bio-resorbable polyester,

b) providing, in a second container, an aqueous phase (AP), comprising a second solvent or solvent mixture S2, comprising water, and an emulsion stabilizing agent,
c) providing a stream of the organic phase (OP) and a stream of the aqueous phase (AP), and joining the stream of the organic phase (OP) and the stream of the aqueous phase (AP), into a joint stream,
d) passing the joint stream through an ultrasonic sound flow-through cell under sonication with a power input of 20 to 50 W per cm3 of the joint stream, to result in an emulsion appearing at an outlet of the ultrasonic sound flow-through cell,
e) removing the first solvent or solvent mixture S1 and the second solvent or solvent mixture S2 by evaporation, or mixing the emulsion with an excess amount of an aqueous extraction phase (EP) to form a combined phase, resulting in removal of the first solvent or solvent mixture S1 from the emulsion; to form nanoparticles, and
f) obtaining the nanoparticles comprising the at least one bio-resorbable polyester by concentration and drying the nanoparticles, to obtain a polymer powder with a Z-Average particle size Dz in the range of 1 to 450 nm and with a polydispersity index PDI in the range of 0.01 to 0.5.