In the present investigation, green synthesis of silver nanoparticles (AgNPs) was carried out using aqueous leaf extract of Argyreia nervosa. The results of the spectral characterisation have revealed that the surface Plasmon resonance band was observed at 421 nm confirms the formation of AgNPs. The Fourier Transform Infra-red Spectroscopy result shows the reduction of silver nitrate into AgNPs by the reduction of different functional groups. Transmission Electron Microscope analysis revealed that the particles are roughly spherical and poly-disperse in shape and size, the particles are within the size range of 10-55 nm. Dynamic Light Scattering revealed that the nanoparticles were also within the range of 10-50 nm, An-AgNPs have a high negative zeta potential value of -38.9 mV. An-AgNPs showed efficient free radical scavenging activity and showed excellent antimicrobial activity. Anti-proliferative and cytotoxic effect of An-AgNPs was carried out by MTT assay against KB oral cancer cells, the IC50 value of An-AgNPs is 58.64 µg/ml. The cell's growth is arrested at the G2/M phase, so the An-AgNPs activated the Caspase 3 pathway which leads to the Apoptosis of KB oral cancer cells. So it is concluded that the green synthesised An-AgNPs have manifold functions.
Keywords: Green synthesis; antibacterial; antioxidant; caspase 3 and in vitro apoptotic activity; spectral characterisation.