Role of polyphenols in plant-mediated synthesis of gold nanoparticles: identification of active components and their functional mechanism

Abstract

In order to learn the active components and their functional mechanism during the plant-mediated synthesis of gold nanoparticles (GNPs), 16 kinds of plants were randomly selected as research objects, and statistical analysis was used to obtain more universal and systematic results. Polyphenols are proved to have the most prominent effect in both reductive and protective capability among all components. The relationship between polyphenols concentration and the protective and reductive capability was further studied in detail. Pyrogallic acid was used as a substitute for polyphenols to elucidate the functional mechanism. The concentration of polyphenols was found to be a critical factor for the preparation of GNPs, and the synergistic competition between phenolic hydroxyl and carbonyl groups caused by the oxidation of polyphenols could affect the particle size and morphology of GNPs. This work can provide excellent guidance for the controllable synthesis of GNPs via the plant-mediated method.

Plasma-Assisted Green Synthesis of ZnO Directly on Polyethylene Terephthalate Fabric

“…The antioxidant activity of PET fabrics functionalized only with a pomegranate peel extract (sample "Extr") or a zinc precursor and a pomegranate peel extract (sample "ZnAc-Extr"), on which ZnO nanoparticles did not form as previously shown by SEM and EDS, have high antioxidant activity due to the presence of phenolic compounds found in pomegranate peel extract [21]. Phenolic compounds are active ingredients and enable natural plant extracts to act as reducing agents in the process of nanoparticle formation [67,68]. During the process of nanoparticle formation, the phenolics are consumed, meaning that their concentrations are reduced, resulting in lower antioxidant activity of either of the nanoparticles or the textiles functionalized with nanoparticles [64][65][66]69].…”

Identification of Marker Molecules in Aqueous Plant Extracts Affecting the Gold Nanostructures’ Morphology and Size

“…Even though phenolic compound play crucial roles during plant extracts mediated synthesis of inorganic nanomaterials (INMs), protein and carbohydrates play roles in stabilization of morphology and size of the INMs. [24] Proteins can also serve as template for INM morphology development. [25,26] Therefore, total protein and total reducing carbohydrate content of the extracts were quantitatively determined.…”

Localized surface plasmon resonance shift of biosynthesized and functionalized quasi-spherical gold nanoparticle systems

“…The different combination leaf extracts contain numerous interacting biochemical compounds. 31,32 These compounds include polyphenols and other organic acids which may exist in various structure forms based on their number of carboxylic, phenolic, cyclic and/or aromatic compounds per molecule. They majorly act as the reducing agents of Au ions when the Au solution is allowed to react with the combination of leaf extracts.…”