Preparation of β-carotene nanoparticles by antisolvent precipitation under power ultrasound

This work seeks to produce β-carotene nanoparticles by ultrasound-assisted antisolvent precipitation and to understand the influences of the various process parameters on the synthesized nanoparticles. At the active concentration of 5–15 mg/ml, 112–141 nm β-carotene particles were precipitated under 1 min ultrasound (18 W); while precipitation without ultrasound resulted in 144–365 nm particles. Without ultrasound, addition of the active solution to water (antisolvent) produced 241 nm particles while addition of water to active solution led to bigger particles, i.e., 519 nm. When the precipitation was carried out under ultrasound, the particle size had only a small increment from 117 to 132 nm. Furthermore, active/antisolvent volume ratio influenced particle size significantly; the particle size decreased from 432 to 223 nm as the active/antisolvent volume ratio decreased from 1:1 to 1:4 without ultrasound. However, the smallest β-carotene particles (117 nm) were precipitated with active/antisolvent volume ratio at 1:2 under ultrasound. Nanoparticles precipitated under ultrasound showed faster dissolution rate in comparison with the raw active and nanoparticles precipitated without ultrasound.