Comparative Study of Biological (Phoenix loureiroi Fruit) and Chemical Synthesis of Chitosan-Encapsulated Zinc Oxide Nanoparticles and their Biological Properties

Abstract

In the present study, the effect of in vitro antioxidant and cytotoxic properties was investigated in the biologically and chemically synthesized zinc oxide (ZnO)- and chitosan (CTS)-encapsulated ZnO (ZnO–CTS) nanoparticles. The nanoparticles were biologically synthesized using Phoenix loureiroi fruit and characterized using Fourier transform infrared, X-ray diffraction, scanning electron microscopy, field emission scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy and ultra violet-diffuse reflectance spectroscopy. The biologically synthesized ZnO–CTS nanoparticles (B-ZnO–CTS) results revealed good chemical structure (H–N–H, O–H, C=O, Zn and O groups), crystalline size (18 nm), morphology (spherical), elemental composition (Zn = 61.10%; O = 25.86%; C = 13.04%) and optical properties (λ = 374 nm; Eg = 3.18 eV). The B-ZnO–CTS also exhibited higher DPPH· (IC50 = 419.32 µg/mL), ABTS·+ (45.61%), nitric oxide (21.28%), hydroxyl radical (77.10%) scavenging activities and superoxide anion radical production (27.89%). The cytotoxicity of B-ZnO–CTS revealed less hemolytic property (2.17%) and inhibited the Caco-2 cancerous cell viability (IC50 = 70.45 µg/mL). In conclusion, biological synthesis presents better prospects in pharmacotherapeutic applications in nano-herbal drug delivery.