Recent progress in biowaste-derived carbon dots for cancer theranostics toward a green solution to toxic metal quantum dots.

Carbon dots (CDs) have emerged as promising nanomaterials for cancer detection and diagnosis due to their unique optical properties, biocompatibility, and surface functionalization capabilities. Metal Quantum dots (QDs) hold great promise for biomedical applications; however, their potential toxicity due to heavy metal ion release and ROS generation raises safety concerns. Subsequently, tremendous research efforts are being conducted toward the development of biogenic CDs synthesized from sustainable bio-sources, aiming towards harnessing their intrinsic biocompatibility and multifunctionality in cancer theranostics. With the increasing demand for safer and eco-friendly nanomaterials in cancer diagnosis and treatment, there is an urgent need for the exploration of biowaste derived CDs representing significant advancement in nanomedicine. In this mini review, we provide a comprehensive overview of recent advancements in utilizing bio waste derived green CDs as cancer biomarkers detectors. We discuss various synthesis methods for CDs, including bottom-up and top-down approaches, highlighting their ability to tailor optical and surface properties for specific applications in cancer detection. Functionalization strategies for enhancing targeting specificity and binding affinity of CDs to cancer biomarkers are also explored, encompassing covalent and non-covalent modifications. Furthermore, we review the applications of CDs in detecting diverse cancer biomarkers, such as proteins, nucleic acids, and small molecules, through fluorescence-based assays. Despite their potential, several challenges such as improving assay sensitivity, specificity, and clinical translation are discussed. Finally, we outline future perspectives, suggesting the integration of CDs into advanced diagnostic platforms for early cancer detection and personalized medicine. Harnessing the unique properties of green CDs holds great promise for revolutionizing cancer diagnostics, enabling early-stage detection, monitoring disease progression, and guiding personalized treatment strategies.