Green synthesis of NiO nanoparticles using Calendula officinalis extract: Chemical charactrization, antioxidant, cytotoxicity, and anti-esophageal carcinoma properties

Abstract

In this study, nickel nanoparticles (NiONPs) have been successfully synthesized in an aqueous medium using the aqueous extract from the leaves of Calendula officinalis. The synthesized NiONPs were characterized using different techniques. According to the XRD analysis, the mean crystal size for NiONPs was found to be 33.17 nm. In addition, SEM images exhibited a uniform spherical morphology with a size of 60.39 nm for the NiONPs. The anti-esophageal carcinoma potentials of C. officinalis leaf aqueous extract, and NiONPs were assessed by the MTT assay against distal esophageal adenocarcinoma (FLO-1), gastroesophageal junction adenocarcinoma (ESO26), human caucasian esophageal carcinoma (OE33), and human esophageal squamous cell carcinoma (KYSE-270) cell lines. This study showed that NiONPs had excellent cell death and anti-cancer effects against esophageal carcinoma cell lines. The IC50 of NiONPs were 380, 263, 229, and 251 µg/mL against FLO-1, ESO26, OE33, and KYSE-270 cell lines, respectively. Among the studied cell lines, the best anti-esophageal cancer activities of NiONPs were gained in the cell line of OE33. The antioxidant activity of NiONPs was investigated using the DPPH test. In the antioxidant test, NiONPs prevented the oxidation of 50% of the DPPH molecules at a concentration of 204 µg/mL. Considering the obtained results, it can be suggested that NiONPs may be administrated as a chemotherapeutic supplement/drug to treat esophageal carcinoma.