Preparation of anionic lipid nanoparticles: Physical properties and stability

Anionic lipid nanoparticles (LNPs) are a lipid-based encapsulation system for poorly water-soluble compounds. Paclitaxel-loaded lipid nanoparticles were prepared by spontaneous emulsification and solvent evaporation (SESE) method with phospholipid, cholesterol, anionic lipids and pacltiaxel. The stability of anionic LNPs was enhanced after lyophilization. Mean particle size and zeta potential of anionic LNPs were measured by electrophoretic light scattering spectrophotometer and drug loading efficiency was evaluated by HPLC. The mean particle size was about 110 nm and loading efficiency was around 70%. DPPA was very efficient for increasing stability because it leads to coulombic repulsive forces of particles. According to cholesterol ratios increased of mean particle size and decreased of drug loading efficiency in the lipid compositions. Also, the low cytotoxicity was observed by MTT assay against B16F10 cells. Anionic LNPs may be a promising drug carrier for the poorly water-soluble drugs.