Tailoring carbon dots for cancer imaging and synergistic therapy

Carbon dots (CDs), as a novel class of fluorescent nanomaterials, have demonstrated significant potential in tumor theranostics due to their outstanding optical properties, excellent biocompatibility, and ease of surface functionalization. However, the clinical translation and functional optimization of CDs remain significantly limited due to the strong dependence of their structural and physicochemical properties on synthetic parameters, particularly the nature of carbon precursors and the strategies adopted for elemental doping. Herein, this review systematically summarizes recent progress in the design and synthesis of CDs derived from diverse precursors, including bulk carbon materials, small organic molecules (such as organic acids, near-infrared dyes, aromatic compounds, and amines), and biomass-based sources (plant-derived substances and animal by-products). Particular attention is given to the influence of precursor molecular structure on particle size, surface chemistry, fluorescence behavior, and biological interactions. Through the integration of diverse synthetic methodologies and structural engineering strategies, this review examines the current requirements for functional refinement and delineates the principal limitations associated with the application of CDs in tumor diagnosis and therapy. Therefore, this review provides a solid theoretical and practical basis for the development of efficient, safe, and clinically applicable carbon dot nanoplatforms, and establishes a foundation for precise and personalized cancer diagnosis and treatment • The review emphasizes how precursor molecular structures and compositions govern the nucleation and carbonization processes of carbon dots (CDs). • The present study aims to compare different synthesis strategies, such as solvothermal, microwave-assisted, and pyrolytic methods, in order to ascertain how reaction conditions influence CD size, crystallinity, and defect states. • The review elucidates the mechanistic interplay between the structural configuration and surface electronic states of CDs governing their photophysical and biological responses..