Versatile Approaches of Quantum Dots in Biosensing and Imaging

Cancer is considered a formidable global health threat, despite substantial strides in diagnosis, detection, and therapeutic strategies. Remarkable progress has been achieved in these realms, yet the survival rates for cancer patients have persisted at suboptimal levels over decades. Acknowledging the need to address the ongoing challenges in cancer survival rates, research efforts are being made to push the boundaries of innovation in diagnostic techniques, bioimaging, and drug delivery technologies. Over the past few years, nano(bio)technology-based approaches have been applied for biosensing and imaging applications to detect biochemical substances in various matrices. Among various nanoengineered particulates, quantum dots (QDs) have been recognized as versatile agents for these applications. QDs, often called artificial atoms, are characterized by the remarkable optical and electrical features which are essential for cytosensing, localized bioimaging and therapeutics. Here in this review, we have discussed various QDs as sensitive and selective agents for precise sensing and imaging of cancer cells. Both electrochemical and optical approaches have been used to describe the cytosensing detection methods. Furthermore, the bioimaging of malignant tumor cells and the drug delivery with therapeutic responses of QDs have also been highlighted. This review also lists the several kinds of QDs that are frequently used for such kinds of applications, such as carbon, graphene, zinc, and other types of hybrid-based QDs. Finally, to shed insight on prospective research, the advantages and potential of QDs are also highlighted. In this article, we also emphasize the limitations and address the difficulties associated with QDs in clinical applications in order to provide insights for potential solutions.