“…Carbon dots (CDs) are carbon-based nanomaterials that have excellent optical properties, high chemical stability, good biocompatibility, and low toxicity; hence, they have broad application prospects in biological imaging, , sensing, – drug delivery, , and photocatalysis. , In this way, CDs have attracted increasing attention of researchers worldwide. , The methods for the preparation of CDs include arc discharge, , laser ablation, electrochemical oxidation, chemical oxidation, microwave-assisted, – and hydrothermal ,, methods. Among them, the hydrothermal method is simple and eco-friendly and does not require a complicated technology or special equipment. , Eco-friendly carbon sources (eggs, banana peel, papaya seeds, milk, , and leaves) are widely used for the preparation of CDs .…”