Quantum dots in the biomedical world: A smart advanced nanocarrier for multiple venues application.

Quantum dots (QDs) are semiconducting nanoparticles having different optical and electrical properties when compared to larger particles. They exhibit photoluminescence when irradiated with ultraviolet light, which is due to the transition of an excited electron from the valence band to the conductance band followed by the return of the exciting electron back into the valence band. The size and material of QDs can affect their optical and other properties too. The QDs possess special attributes like high brightness, protection from photobleaching, photostability, color tunability, low toxicity, low production cost, a multiplexing limit, and a high surface-to-volume proportion, which make them a promising tool for biomedical applications. Here, in this study, we summarize the utilization of QDs in different applications including bioimaging, diagnostics, immunostaining, single-cell analysis, drug delivery, and protein detection. Moreover, we discuss the advantages and challenges of using QDs in biomedical applications when compared with other conventional tools.