(303b) Continuous Synthesis of Drug Particles through Spray-Drying of Nano-Emulsion
AIChE Annual Meeting
2023
2023 AIChE Annual Meeting
Particle Technology Forum
Poster Session: Particle Technology Forum
Wednesday, November 8, 2023 - 3:30pm to 5:00pm
In this study, the âemulsion spray-drying methodâ was proposed as a novel method for the nanoparticle synthesis. First, nano-sized oil in water (O/W) emulsions with oil-soluble drugs were prepared. Spraying the O/W emulsions generated nano-sized oil droplets within the water droplets. The nano-sized oil droplets dried then to produce fine particles. In this study, nifedipine (NFD) and polyvinylpyrrolidone were used as model powders. Chloroform and Tween 80 were used as the oil component and the surfactant, respectively. These were mixed and stirred with mechanical external force to generate O/W emulsions. The obtained O/W emulsions were confirmed to have monodisperse fine oil droplets with the size of 165 nm. The O/W emulsions were spray-dried, obtaining the NFD particles with the size of ca. 122 nm. To verify the micritization by the emulsion spray-drying method, chloroform solutions of NFD without emulsion were spray-dried. The NFD particles obtained by spray-drying chloroform solutions were 2.5 µm in diameter, demonstrating that fine particles can be obtained by emulsion spray-drying.
Furthermore, ouzo emulsion, which is the self-emulsification method, was investigated to improve the particle yield. Ouzo emulsions are generated through the mixing of oil, water, and co-soluble surfactants. Co-soluble surfactants are well soluble in both oil and water. Phenytoin (PHT), 1-hexanol, and ethanol were used as model powders, the oil component, and the co-soluble surfactant, respectively. These were just mixed to generate ouzo emulsions. The obtained ouzo emulsions had monodispersed fine oil droplets with the size of 7.06 nm. The ouzo emulsion was spray-dried, obtaining the PHT particles with the size of ca. 300 nm. Here, high yields of 2.2 g/min were achieved compared with spray-drying of O/W emulsions. 1-hexanol solutions of PHT without emulsion were also spray-dried. The PHT particles obtained by spray drying a 1-hexanol solution were 1 µm in diameter, demonstrating that fine particles can be obtained by spray-drying of ouzo emulsions. Moreover, dissolution tests were performed to evaluate the solubility of the three PHT particles, including the raw powder. The PHT particles obtained via the spray-drying of ouzo emulsions were confirmed to indicate the highest dissolution rate.
In summary, the spray-drying of O/W emulsions with chloroform and ouzo emulsions with 1-hexanol demonstrated the production of fine drug particles.