Green synthesis of gold nanoclusters using seed aqueous extract of Cichorium intybus L. and their characterization

The present study reports the green synthesis of gold nanoparticles (AuNPs) by Cichorium intybus L. (chicory) aqueous seed extract and their total polyphenol content (TPC), ferric reducing antioxidant power, and photocatalytic activities as well as antiproliferative effect in C2C12 myotubes. The formation of AuNPs was achieved by reacting the extract with 1 mM final concentration of hydrochloroauric acid trihydrate (HAuCl 4 ·3H 2 O) and confirmed by UV–visible spectroscopy. DLS particle size analyzer and TEM analysis showed mostly spherical crystals of around 1.7–3.2 nm (zeta potential, − 5.97) that converged to form a uniform collection of 20–40 nm clusters with irregular contour (zeta potential, − 19.7). In XRD analysis, AuNPs produced strong signal for gold; and the presence of extract components on AuNP surfaces was confirmed by FT-IR, ESD, and HPLC. TPC and the antioxidant activity were equivalent to about 1.2 mg of Gallic acid and 4.3 mM Fe2+ , per gram AuNP, respectively. The cytotoxic effect of AuNPs in C2C12 myotubes was examined by MTT assay in which higher concentrations of fraction “f 1 ”, separated according to size by sucrose density gradient centrifugation, showed anti-proliferative activity in C2C12 myoblast cells. Despite their nontoxic behavior, AuNP nanoclusters possessed good antioxidant and photocatalytic activities.