Optimization of processing parameters for the development of Ficus religiosa L. extract loaded solid lipid nanoparticles using central composite design and evaluation of antidiabetic efficacy

The aim of the present work was to optimize processing parameters for the preparation of Ficus religiosa L. extract loaded solid lipid nanoparticles (SLN) using central composite design. Optimization was carried out using four factors such as homogenization speed, homogenization time, sonication time and sonication intensity and three responses studied were particle size, polydispersity index (PDI) and zeta potential to obtain a SLN batch with lesser particle size, optimum PDI and higher zeta potential. Further, optimized batch was characterized for entrapment efficiency, surface morphology, in-vitro release and kinetics, fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), powder Xray diffraction (PXRD) and stability over 6 months. From the results, it was observed that increase in homogenization speed and time decreased particle size and PDI with increase in zeta potential value. Increase in sonication time up to 5 min decreased particle size and further increase had no effect on particle size. Sonication intensity had very little effect. DSC and PXRD showed reduced crystallinity of extract in SLN form. Also, the optimized batch had stability over 6 months. Further, SLN significantly reduced diabetes induced higher levels of blood glucose and increased diabetes induced lower level of plasma insulin.