The era of graphene-based quantum dots

Nanomaterials are generally considered as the particles whose size ranges from 1 to 100 nm. They are known to impart unique physical and chemical properties compared to bulk materials, with enhanced surface to volume ratio. In the last few decades, numerous nanomaterials have been synthesized for various biomedical applications and therapeutics. Among them, nanomaterials based on carbon and the allotropes of carbon have gained huge recognition in the biomedical field because of their increased mechanical strength and their imaging properties. Among them, carbon-based quantum dots are a recent group pf carbon nanomaterials that has attracted many researchers and proved to be potential competitors to the existing quantum dots due to their novel properties. Carbon based quantum dots are classified into two divisions, namely graphene quantum dots (GQDs) and carbon quantum dots (CQDs), which are emanating quantum dots with newly developed properties due to their effect of quantum confinement. They manifest remarkable biocompatibility, decreased toxicity, and simple functionalization. Thus, in this chapter, different biomedical applications, such as bioimaging, drug delivery, gene therapy, cancer therapy, and biosensing of CQDs and GQDs are described. The present challenges and future perspectives of CQDs and GQDs for biomedical applications are defined in conclusion.