OPTIMIZATION OF NANOCARRIER PREPARATION PROCEDURE BASED ON LIQUID CRYSTALLINE PHASE

PURPOSE: The means of this work was the validation and optimization of nanocarrier preparation procedure based on liquid crystalline phase nanodispersion. METHODS: Formulations were prepared following Vicentini et al. 2012, using oleic acid, monoolein and cationic polymer PEI at 1.0% in the oil phase and 0.1M Tris-HCL, pH 6.5 containing 1.5% (w/w) of poloxamer 407 in the aqueous phase (1). The aqueous phase was added in oil phase and the resulting formulation was lowed to equilibrate at room temperature for 24 hours. To obtain the dispersion, the gel with excess water was vortex, sonicated, centrifuged and filtrated. The influence of sonication time, centrifugation and filtration on the particle size, zeta potential and polydispersity were evaluated. In the first group (G 1) the formulation was sonicated for 2 min; the second group (G 2) the formulation was sonicated for 4 minutes and centrifuged during 10 min at 1901 g; and the third group (G 3) the formulation was sonicated for 4 min, centrifuged during 10 minutes at 1901 g and filtered using a membrane of 0.45 µm pores. The resulting preparations were characterized by dynamic light scattering (DSL). DLS method was performed in Zetasizer 3000 HSa (Malvern Instruments) using HeNe laser operating at 10 mW and 633 nm with a 90∫ angle, were obtained measures of the internal diameter of the particles, zeta and the index of polydispersity. RESULTS : The results showed values of G1 (319.8nm; -2.65; 0.584), G2 (177.2nm;-4.27; 0.324) and G3 (168.9nm;-3.57; 0.259) of particle size, zeta and polydispersity, respectively. There was no significant difference between G2 and G3. However, centrifugation process was important to the obtainment of nanodispersion with reduced particle size. CONCLUSION : The optimization of nanodispersions based on centrifugation process shown to be an important tool to obtain smaller particles. The following step will be the application of these smaller particles in transfection cells studies.