Green synthesis of a MnO-GO-Ag nanocomposite using leaf extract of Fagonia arabica and its antioxidant and anti-inflammatory performance

This research work includes the green synthesis of silver and graphene oxide doped manganese oxide nanocomposites (NCs) using Fagonia arabica, which is commonly found in Asian countries and widely grown in deserts. Fagonia arabica is a medicinal herb used for the treatment of a variety of diseases. Fagonia arabica shows efficient anti-inflammatory, antimicrobial activity and antioxidant properties. Manganese oxide (MnO) NPs were synthesized by a green synthesis method using leaf extract of Fagonia arabica. The synthesized manganese oxide nanoparticles (NPs) were then used to form manganese oxide composites coupled with graphene oxide (GO) and silver (Ag). The main composite synthesized in this research work is MnO-GO-Ag NCs. All the synthesized NPs and composites were then characterized by SEM, XRD, EDX and ultra-violet–visible spectroscopy. The anti-inflammatory activity of the manganese oxide NPs and their MnO-GO and MnO-GO-Ag composites were checked by UV-visible spectroscopy and the obtained results were compared with the standard Diclofenac Sodium. The antioxidant activity of MnO-GO-Ag shows a higher scavenging potential than the standard ascorbic acid. SEM analysis was performed to check the size and morphology of the obtained product. The XRD analysis confirmed the purity and crystallinity of synthesized MnO-GO-Ag NCs. EDX spectra showed the peaks for C, O, Ag and Mn, indicating the presence of these elements in our desired composite. For anti-inflammatory activity, the MnO-GO-Ag NCs showed percentage inhibitions of 34.15 and 81.71%, having an IC₅₀ values of 0.15 and 0.23, at 0.1 and 0.5 mg/mL concentrations, respectively. MnO-GO-Ag showed percentage scavenging efficiencies of 59.84 and 74.48% at concentrations of 0.3 and 0.5 mg/mL, respectively, while the standard (ascorbic acid) showed scavenging potentials of 44.22 and 58.42% at similar concentrations. The MnO-GO-Ag NCs showed lower IC₅₀ values, thus exhibit the high efficiency of the NCs for anti-inflammatory and antioxidant activities.