Box-Behnken Design for Optimization of Nanostructured Lipid Carrier Sonication Conditions from Mixtures of Palm Stearin and Palm Olein

In this study we aimed to determine the optimum conditions for sonication in the manufacture of nanostructured lipid carriers (NLC). NLC were developed using a mixture of palm stearin and palm olein, water, and tween as surfactants. The optimum conditions of NLC is defined as having a size below 200 nm, a zeta potential of +30 mV, and a polydispersity index below 0.5. We used response surface methodology with a Box- Behnken experimental design to obtain the optimum conditions for the production of NLC. The independent variables used in this study were amplitude (X-1, kHz), pulse on pulse off (X-2, minute), and time of sonication (X-3, minute), each having three levels. The zeta potential (Y-1, mV), polydispersity index (Y-2), and particle size (Y-3, nm) were used as the dependent variables. The dependent variables were determined by dynamic light scattering using a Malvern Zetasizer Nano ZS. The closest to optimum formulation was obtained at a combination of 35 kHz amplitude, pulses on 9 pulses off 3, and 3 min 25 seconds sonication. This regime resulted in the production of NLCs with a particle size 127.9 nm, a polydispersity index of 0.191, and a zeta potential of -27.3 mV.