Green-Synthesized Gold Nanoparticles Using <i>Ambrosia artemisiifolia</i> : Insights into DNA Interaction, Protein Binding, Enzyme Mimicry, Anticancer Potential, and Dye Degradation Efficiency

The use of plant extracts in green synthesis has opened avenues for the development of nanoparticles with unique biological properties. This study focuses on the green synthesis of gold nanoparticles (AuNPs) using <i>Ambrosia artemisiifolia</i> (AA) leaf extract and evaluates their effectiveness in biomedical applications and catalysis. Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-vis), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), TEM, and X-ray photoelectron spectroscopy (XPS) studies are used to characterize the developed NPs. Following initial characterization, biophysical techniques are used to confirm the DNA and protein binding ability of the developed nanoparticles. The results of UV-metric titration and fluorescence spectroscopic titration confirm the binding efficacy of the developed nanoparticles to DNA and protein, respectively. The anticancer activity of AA-AuNPs against HeLa cancer cells is evaluated using the MTT assay, alongside HEK-293 normal cells, demonstrating promising therapeutic potential with minimal toxicity toward normal cells. Concurrently, the developed nanoparticles exhibited effective phenoxazinone mimicking activity. Furthermore, these nanoparticles exhibit a remarkable ability to degrade toxic dyes, achieving over 90% degradation within an 80 min time frame. These dual functionalities position AA-AuNPs as viable candidates for both biomedical and environmental remediation applications.