Lentil Extract-Mediated Ag QD Synthesis: Predilection for Albumin Protein Interaction, Antibacterial Activity, and Its Cytotoxicity for Wi-38 and PC-3 Cell Lines

Abstract

Recent focus has been directed toward semiconductor nanocrystals owing to their unique physicochemical properties. Nevertheless, the synthesis and characterization of quantum dots (QDs) pose considerable challenges, limiting our understanding of their interactions within a biological environment. This research offers valuable insights into the environmentally friendly production of silver quantum dots (Ag QDs) using lentil extract and clarifies their distinct physicochemical characteristics, previously unexplored to our knowledge. These findings pave the path for potential practical applications. The investigation of the phytochemical-assisted Ag QDs’ affinity for BSA demonstrated modest interactions, as shown by the enthalpy and entropy changes as well as the associated Gibbs free energy during their association. Steady-state and time-resolved fluorescence spectroscopy further demonstrated a transient effect involving dynamic quenching, predominantly driven by Forster resonance energy transfer. Additionally, the study highlights the potential broad-spectrum antibacterial activity of Ag QDs (<5 nm, a zeta potential of −3.04 mV), exhibiting a remarkable MIC value of 1 μg/mL against Gram-negative bacteria (E. coli) and 1.65 μg/mL against Gram-positive bacteria (S. aureus). They can readily enter cells and tissues due to their minuscule size and the right chemical environment. They cause intracellular pathway disruption, which leads to cell death. This outcome emphasizes the distinctive biocompatibility of the green-synthesized Ag QDs, which has been confirmed by their MTT assay-based cytotoxicity against the PC-3 and Wi-38 cell lines.