Carbon-based designer and programmable fluorescent quantum dots for targeted biological and biomedical applications

Carbon dots (CDs) are emerging nano-biomaterials owing to their exceptional optical and physico-chemical properties. In recent years, they have gained attention due to some of their distinctive applications in biological science, including bio-imaging, drug delivery, biosensing, and cancer therapy. Depending on the material, desired fluorescence, and expected size, these carbon-based fluorescent nanoparticles can be made using a variety of chemical and natural compounds and varying methodologies. Owing to the unique tunable optoelectronic properties, they exhibit properties including size-tunable emission, excitation-dependent emission, and solvent-dependent emission. We present here a brief perspective on their synthesis, factors regulating their fluorescence behavior, unique characteristics, advantages, limitations, and very focused biomedical applications. We conclude with a brief discussion on future innovations to make the carbon dots ready for real-world biomedical applications.