Carbon dots as nano-pioneers: A critical review on advances in fabrication and antibacterial mechanism

The global rise in antibiotic resistance advocates the urgent need for exploring novel antibacterial therapies, including both innovative antibiotics and non-antibiotic therapy. This review outlines a roadmap for advancing nanotechnology-based ultra-small antibacterial agents like carbon dots (CDs) to combat multidrug-resistant pathogens. CDs, zero-dimensional carbon nanomaterials measuring under 10 nm in size, are gaining attention for their potential applications across various fields, including energy storage, electronics, chemistry, and biomedicine. With properties like tunable photoluminescence (PL), customizable surface functionalities, and efficient photo-electron transport, CDs can achieve potent antibacterial effects through mechanisms such as reactive oxygen species (ROS) generation, membrane disruption, and intracellular interactions. This review presents a critical analysis of the overview of CDs, including the various processes involved in their fabrication, the antibacterial action and mechanism of CDs, factors impacting CDs antibacterial activity, current challenges, research gaps, and potential future directions for the long-term sustainable development and implementation of CDs in antimicrobial innovations. Current challenges, including scalability, biocompatibility, sustainability, and regulatory concerns, are reviewed, along with insights on how addressing these gaps could position CDs as sustainable alternatives to antibiotics in antimicrobial technology.