AFM has been recently employed as a major microscopic tool to observe SLN on size and morphology (Ruktanonchai et al.,2008, in press). This is due to many advantages for the detection and characterization of heterogeneous populations with regards to the amount of material required for a study as well as to the level of information that can be acquired. The morphology of SLN of both lipid concentrations after the preparation was also observed by AFM (Fig. 3) and SEM (Fig. 4).