Solid Lipid Nanoparticles from Platonia insignis Seeds, a Brazilian Amazon Fruit: Characterization, In Vitro and In Vivo Toxicological and Antioxidant Activities

Abstract

Solid Lipid Nanoparticles (SLNs) are drug delivery systems with important advantages over conventional nanosystems. Considering previously reported pharmacological and physicochemical properties of Platonia insignis seed butter (BBI), this work aimed at developing, characterizing and performing toxicological and antioxidant studies of SLNs produced from BBI. The GC-MS analysis identified palmitic and oleic acids as the major compounds. Three SLN prototypes were developed through high-shear homogenization followed by ultrasonication. During a 180-day stability evaluation, the formulation SLN/TW-1.5 presented greater stability since pH was around 6.0, as well as a lesser variation of the PdI (Polydispersity Index), particle size and Zeta Potential (ZP), confirmed with Raman Spectroscopy and Atomic Force Microscopy (AFM). The CC50 in macrophages was around 249.4 µg∙mL−1 for BBI, whereas the CC50 value for SLN/TW-1.5 was 45.2 µg∙mL−1. Electron Paramagnetic Resonance (EPR) showed a marked in vitro antioxidant activity for BBI and SLN/TW-1.5. After in vivo SLN/TW-1.5 administration in Zophobas morio larvae, assessment of reduced glutathione (GSH), nitrite (NO2−) and myeloperoxidase (MPO) demonstrated antioxidant activity. Thus, the intrinsic physicochemical properties of BBI allowed the development of an optimized nanoformulation with high stability indexes, besides the great potential for antioxidant applications.