Yaping Zhao

Nanoencapsulation of Lutein with Hydroxypropylmethyl Cellulose Phthalate by Supercritical Antisolvent

Lutein was nano-encapsuled with hydroxypropylmethyl cellulose phthalate (HPMCP) to maintain its bioactivity and to avoid thermal/light degradation. Supercritical antisolvent precipitation was applied to prepare lutein/HPMCP nano-capsule. The effects of several operating parameters on the yield, lutein loading, encapsulation efficiency, particle size and particle size distribution of the nanocapsule were investigated. The mean diameter of nanocapsules ranged from 163 nm to 219 nm under appropriate experimental conditions. The result of scanning electron microscope showed that the nanocapsules were nearly spherical. The highest yield reached 95.35% when the initial concentration of lutein was saturated. The highest lutein loading of 15.80% and encapsulation efficiency of 88.41% were obtained under the conditions of 11 MPa, 40°C and CHPMCP:Clutein = 5:l. The results may promote the application of lutein in food industry.

Supercritical Antisolvent-based Technology for Preparation of Vitamin D3 Proliposome and Its Characteristics

Abstract Vitamin D 3 (VD 3 ) proliposomes (VDP), consisted of hydrogenated phosphatidycholine (HPC) and VD 3 , were prepared using supercritical anti-solvent technology (SAS). The effects of operation conditions (temperature, pressure and components) on the VD 3 loading in VDP were studied. At the optimum conditions of pressure of 8.0 MPa, temperature of 45°C, and the mass ratio of 15.0% between VD 3 and HPC, the VD 3 loading reached 12.89%. VD 3 liposomes (VDL) were obtained by hydrating VDP and the entrapment efficiency of VD 3 in VDL reached 98.5%. The morphology and structure of VDP and VDL were characterized by SEM (scanning electron microscope), TEM (transmission electron microscope) and XRD (X-ray diffractometer). The structure of VD 3 nanoparticles in HPC matrix was formed. The size of VDL with an average diameter of about 1μm was determined by dynamic light scattering instrument (DLS). The results indicated that VDP can be made by SAS and VDL with high entrapment efficiency can be formed easily via the hydration of VDP.

Preparation of coenzyme Q10 liposomes using supercritical anti-solvent technique

Coenzyme Q10 (CoQ10) proliposomes were prepared using the supercritical anti-solvent (SAS) technique to encapsulate CoQ10. The mixture of cholesterol and soya bean phosphatidylcholine (PC) was chosen as wall materials. The effects of operation conditions (temperature, pressure and components) on the recovery of CoQ10 and the CoQ10 loading in CoQ10 proliposomes were studied. At the optimum conditions of pressure of 8.0u2009MPa, temperature of 35°C, the weight ratio of 1/10 between CoQ10 and PC, and the weight ratio of 1/3 between cholesterol and PC, the CoQ10 loading reached 8.92%. CoQ10 liposomes were obtained by hydrating CoQ10 proliposomes and the entrapment efficiency of CoQ10 reached 82.28%. The morphologies of CoQ10 proliposomes were characterized by scanning electron microscope, and their solid states were characterized by X-ray diffractometer. The structures of CoQ10 liposomes were characterized by transmission electron microscope. The particle size distribution of CoQ10 liposomes was determined by dynamic light scattering instrument. The results indicate that CoQ10 liposomes with particle sizes about 50u2009nm can be easily obtained from hydrating CoQ10 proliposomes prepared by SAS technique.

Rapid and Continuous Production of LiFePO4/C Nanoparticles in Super Heated Water

Abstract A rapid and continuous method for production of LiFePO4/C nanoparticles in super heated water is described, wherein soluble starch was used as carbon precursor. The effects of pH, flow rate, temperature, and pressure on the formation of LiFePO4/C particles were investigated. Results showed that the pH value was the key factor on the formation of phase pure LiFePO4, which only formed at pH = 7; the LiFePO4/C occurred as particles with about 70-200 nm size and LiFePO4 was covered by a thin carbon layer; higher flow rate, higher pressure, and lower temperature led to smaller particles of LiFePO4/C.

Production of Submicroparticles of β-Sitosterol Using an Aerosol Solvent Extraction System

Abstract The submicroparticles of β-sitosterol were produced by using an aerosol solvent extraction system (ASES) and characterized by scanning electronic microscope (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FT-IR) analysis. The effects of operational parameters including pressure, temperature, solution concentration, and ratio of flow rate (CO 2 /solution, r ) on particle size (PS), yield, and morphology were investigated. The results showed that microparticles of β-sitosterol (less than 1000 nm size and larger than 70% yield) could be obtained at 10-15 MPa, 35–50°C, 15 mg·ml −1 , 10/1( r ); β-sitosterol particles were found to occur as three mophologies: flakes, rods, and spheres by varying ratio of flow rate or solution concentration. In contrast, the crystallinity of β-sitosterol decreased, whereas its molecular structure remained almost unchanged after being ASES-treated. Therefore, ASES was an effective method to produce submicroparticles of β-sitosterol.

Preparation of Nano-curcumin with Enhanced Dissolution Using Ultrasonic-Assisted Supercritical Anti-solvent Technique

Abstract Curcumin is the main gradient of “Turmeric” a famous Indian spice and food additive. The marvelous nutritional and medicinal effects of curcumin made it a good alternative to some conventional drugs and food flavoring or coloring materials. However, the low solubility of curcumin is a challenging hindrance which should be seriously addressed. In this work, we prepared nano-curcumin with enhanced aqueous dispersion and dissolution rate. Ultrasonic-assisted supercritical anti-solvent (UA-SAS) technique was used to convert the commercial curcumin to uniform distributed nano-particles with the average size of 20 nm and yielding of 65%. The effect of process parameters including pressure, temperature, solution flow rate, and nature of organic solvent on the average particle size and yielding of products was investigated. The morphology, size, and crystalline pattern of processed curcumin particles were characterized by scanning electron microscopy, mean particle size analyzer, and X-ray diffraction. The champion specimen was achieved when the supercritical fluid was employed at 16 MPa and 35°C. Aqueous suspension of processed nano-curcumin can be stable for more than 2 months. In vitro dissolution experiments showed a remarkable enhancement in dissolution rate of UA-SAS-treated curcumin respecting to the commercial curcumin powder.