Kolanut (Cola nitida) Mediated Synthesis of Silver-Gold Alloy Nanoparticles: Antifungal, Catalytic, Larvicidal and Thrombolytic Applications

摘要

This study investigated use of leaf, seed, seed shell and pod extracts of Cola nitida for the green synthesis of silver-alloy nanoparticles (Ag-AuNPs). The Ag-AuNPs formed were dark brown with maxima absorbance in the range of 497-531 nm. FTIR peaks at 3290-3396 and 1635-1647 cm(-1) showed that proteins were the capping and stabilization molecules for the synthesis of Ag-AuNPs. While leaf, seed and seed shell extract-mediated Ag-AuNPs had near spherical morphology, anisotropic structures of sphere, rod, hexagon and triangle were formed by pod extract. The polydispersed particles were 17-91 nm in size, with crystalline characteristics and prominent presence of Ag and Au in the EDX spectra. Ag-AuNPs inhibited growth of Aspergillus flavus, A. fumigatus and A. niger by 69.51-100 %. Exposure of Anopheles mosquito larvae to Ag-AuNPs resulted in 80-100 % mortality in 24 h. Catalytic degradation of > 90 and > 60 % were obtained for malachite green and methylene blue respectively after 24 h. The particles displayed potent blood anticoagulant and thrombolytic activities, indicative of their potentials in the management blood coagulation disorders. This study showed that C. nitida can be used for green synthesis of Ag-AuNPs, which is the first report of its kind.