Effects of Surfactants and Lipids on the Preparation of Solid Lipid Nanoparticles Using Double Emulsion Method

In this article, double emulsion method was used to prepare solid lipid nanoparticles (SLN). Different kinds of SLN were synthesized by changing the species and contents of lipids and surfactants in microemulsion. The effects of the hydrophobic chain length of surfactant inside and surfactant outside, the type of lipid and the ratio of Span/Tween on SLN were systematically investigated. Dynamic light scattering (DLS) and zeta potential were applied to study the change trend of particle size and surface charge of SLN. The DLS results show that the size of SLN increases as the hydrophobic chain length of lipid enhances, and decreases with the increase of hydrophobic chain length of Tween or that of Span or the ratio of Span/Tween. And the absolute value of zeta potential as well as the stability of SLN dispersion decreases as the hydrophobic chain length of Span or lipid increases, and increases when the hydrophobic chain length of Tween or the ratio of Span/Tween increases.