Emerging Antineoplastic Plant-Based Gold Nanoparticle Synthesis: A Mechanistic Exploration of their Anticancer Activity Toward Cervical Cancer Cells

In this work, gold nanoparticles (AuNPs) were synthesised using the fresh leaves extract of Pongamia pinnata (PLE) and characterized using various analytical techniques such as UV–visible spectroscopy, TEM, SEM, EDX, and XRD. UV–Visible spectra showed surface plasmon resonance (SPR) peaks in the range of 520–540 nm signifying the synthesis of colloidal AuNPs stabilised by PLE. Further, we investigated the cytotoxic effects of AuNPs against human cervical cancer cell line (HeLa). MTT assay screened IC50 value of 200 μg/mL at 24 h for AuNPs formed at varying HAuCl4 concentration. Flow cytometry measurements using H2DCFDA showed that the toxicity of AuNPs was attributed to the generation of reactive oxygen species (ROS). Besides, the in vitro anticancer activities of AuNPs were studied in HeLa cells by several assays which resulted in altered cell morphology, reduced potential of wound healing, inactive mitochondria due to loss of mitochondrial membrane potential (MMP) and cell cycle arrest. AuNPs showed dose-dependent selective toxicity towards HeLa cells and were non-toxic against human embryonic kidney cell line (HEK293). The study revealed an efficient, ecofriendly and simple method for synthesis of multifunctional AuNPs using green synthetic approach with high anticancer potential for cervical cancer cell line.