Preparation and Evaluation of In-vitro Release and Cytotoxicity of Indigofera zollingeriana Crude Leaf Extract-loaded Nanoemulsion

Abstract

This study aimed to prepare and investigate the in-vitro release and cytotoxicity effect of an Indigofera zollingeriana crude leaf extract-loaded nanoemulsion formulation. Initially, I. zollingeriana leaf extract was extracted and the ternary phase diagram was constructed to select the nanoemulsion formulation. The nanoemulsion was prepared with a combination of oil, surfactant, and water using a low-energy emulsification method. The formulation was characterized according to droplet size, polydispersity, zeta potential, morphology, and physical stability. In-vitro release and cytotoxicity were investigated to determine the efficacy of the nanoemulsion. Based on the results, a stable formulation (no phase separation) with a ratio of 5:10:85 (sunflower seed oil: surfactant: water) was obtained with droplet size, polydispersity index (PDI) and zeta potential of 160.5 nm, 0.262 and -31.1 mV, respectively. Morphology study revealed that particles of the nanoemulsion were spherical with diameters ranging from 95.97 to 148.31 nm. In-vitro release study showed fast release in the first 3 h at pH 7.4. The percentage cumulative release of the crude extract was obtained by up to 86.50% for 24 h. Cytotoxicity study of the nanoemulsion formulation showed moderate and mild toxicity against lung cancer (A549) and breast cancer (MCF-7) cell lines, respectively.