Preparation of zein nanoparticles by supercritical CO_2 anti-solvent precipitation

Zein nanoparticles was prepared from the acetone-DMSO mixed solution of zein using the supercritical CO2 anti-solvent precipitation(SAS).The effects of temperature,pressure,zein solution concentration,flow rate of supercritical CO2 and solution were studied.SEM,Particle Size Analyzer,TGA,DSC were used to characterize the products.The result showed that the zein nanoparticles with good sphericity and narrow size distribution could be prepared by SAS precipitation,and the mean diameters of the microspheres ranging between 160nm and 400nm could be obtained.Temperature,pressure and the concentration of the solution can influence the size of products,so the different size and distribution requirements of zein nanoparticles can be prepared through the selection of different process combinations.The TG analysis curves and DSC thermogram showed that the blank zein nanoparticles were more stable than the law zein.