Comparative studies of silibinin contained solid lipid nanoparticles prepared by two methods

AIM: To evaluate the potential of the preparatory methods of solid lipid nanoparticles (SLN) carrying silibinin (SIL) extracted from traditional Chinese medicinal herbs, and to study the physicochemical characteristics of the SIL-SLN produced by 2 different methods. METHODS: SIL-SLN was prepared by ultrasonication or high pressure homogenization. Transmission electron microscopy was employed to study the shape. Particle characterization system and zeta potential analyzer were used to study the particle diameter and zeta potential of SLN in suspension. The entrapment efficiency was determined by sephadex gel chromatography and high-performance liquid chromatography (HPLC). The stability of SLN was also studied. RESULTS: The SIL-SLN prepared by ultrasonication was platelet-shaped and irregular, and the SIL-SLN prepared by high pressure homogenization was spherical and regular in shape. The particle diameters of SIL-SLN prepared by ultrasonication and high pressure homogenization were (165±7) nm and (157±6) nm separately (P0.05). The Zeta potentials were (-28.35±2.72) mv and (-35.36±2.68) mv separately (P0.001). The entrapment efficiencies were (90.59±0.89)% and (95.64±1.33)% (P0.001) separately. SIL-SLN prepared by high pressure homogenization showed sufficient long-term stability with only slight particle growth (P0.05) after storage at room temperature for 4 weeks. CONCLUSION: High pressure homogenization is demonstrated to be a more suitable method than ultrasonication to prepare the smaller, steadier and highly incorporated SIL-SLN.