Arginine-derived green-synthesized carbon dot@copper sulfide nanorods (CD@CuS) as a potent and biocompatible antibacterial agent: Experimental and computational insights

The emergence of multidrug-resistant bacteria underscores the critical need for innovative antibacterial agents. This study presents the green synthesis of a carbon dot@copper sulfide nanorod (CD@CuS) using arginine-derived carbon dots (CDs) and eco-friendly CuS nanorods. Structural characterization via FTIR, XRD, TEM, UV–Vis, and XPS confirmed successful nanocomposite formation. The CD@CuS exhibited potent antibacterial activity against Escherichia coli (E. coli), with a 25 mm inhibition zone, attributed to reactive oxygen species (ROS) generation and membrane disruption. At 100 µg/mL, the nanocomposite achieved significant bactericidal effects while maintaining >80% mammalian cell viability. Hemocompatibility assays (ISO 10993-4) revealed a safe hemolytic threshold of 156.25 µg/mL. Integrative computational approach via DFT and docking supports the experimental work and increases the mechanistic understanding of CuS bioactivity toward E. coli. Combining high efficacy with low cytotoxicity, CD@CuS demonstrates promise as a biocompatible alternative to conventional antibiotics, addressing the challenge of bacterial infections.