Preparation, characterization, and in vitro release investigation of lutein/zein nanoparticles via solution enhanced dispersion by supercritical fluids

► Lutein/zein nanoparticles were prepared by SEDS process. ► The effects of variables on the properties of the nanoparticles were elucidated. ► The nanoparticles with a good spherical shape were developed at 45°C/10MPa. ► Lutein release profile in the nanoparticles displayed a near zero-order release. ► The result indicates that the nanoparticles played a role in controlled release. Solution enhanced dispersion by supercritical fluids (SEDS) was applied for the production of lutein/zein nanoparticles. The effects of the process variables on the morphology, drug loading, entrapment efficiency, and mean particle size of the nanoparticles were investigated. The results showed that the nanoparticles with high drug loading and high entrapment efficiency were prepared by SEDS process. Temperature, pressure, ratio of lutein/zein, and solution flow rate can influence the morphology, drug loading, entrapment efficiency, and the mean particle size of the lutein/zein nanoparticles. The lower temperature and solution flow rate coupled with high pressure, favor smaller and more regular spheres. The initial and overall drug release behavior of the samples was tested. The initial burst release was hardly observed in the nanoparticles processed at 45°C/10MPa. Furthermore, lutein release profile displayed a near zero-order release, which implied that the nanoparticles played a role in controlled release of lutein.