Rhynchosia rufescens AgNPs enhance cytotoxicity by ROS-mediated apoptosis in MCF-7 cell lines.

The present study deals with the synthesis of silver nanoparticles (AgNPs) from Rhynchosia rufescens and to evaluate its cytotoxic effect mediated through induced apoptosis. The reduction and capping of phytoconstituents was confirmed using FTIR demonstrating O-H and C-H stretching at different peaks. The size and the shape of the particle were determined using scanning electron microscopy (SEM) illustrating 1 μm to 100 nm in size and the composition of compounds in the AgNPs were revealed using XRD and EDX. The results of the antioxidant assays revealed that the synthesized AgNPs had significant radical scavenging potential in dose-dependent inhibition with 22-64% for DPPH and 25-41% for ferric reducing antioxidant power assay at the concentrations of 20-100 μg/ml. Further, the synthesized AgNPs demonstrated potent cytotoxic activity against human breast cancer (MCF-7) cell line with an IC50 value of 26 ± 1.0 μg/ml by the MTT assay. Cytotoxicity was confirmed using AO/EtBr and DAPI staining method where nuclear condensation and fragmentation of cancer cells was observed after treatment with nanoparticle. The results were further confirmed by flow cytometry analysis which revealed the occurrence of apoptosis during the S phase in cell cycle exposing the potential of the AgNPs against MCF-7 cancer cell. From the results, we conclude that the synthesized AgNPs from Rhynchosia rufescens exhibited multifunctional properties. Graphical abstract.