Quantum dots for sensing applications

Synthetic nanoscale semiconductor nanocrystals, aka quantum dots (QDs), are excellent fluorophore candidates for sensing technology due to their spectacular optical and electronic characteristics. Because of their size range (2–10nm), QDs exhibit high quantum efficiency and possess high extinction coefficients, wide absorption spectrum, emission at narrow different symmetrical bands, properties of quantum confinements, and resistance to chemical degradation. With these features, QDs are utilized in numerous technological fields such as display technology, bioimaging, diagnostic, and biomolecular interactions. In addition, QDs are widely used in in vitro studies to trace multiple biological targets simultaneously without any complex instrumentation. Also, the unique optoelectronic features of QDs lead to the extensive use of QDs in sensor development. This chapter provides fundamental information about synthesis, classification, and characterization of QDs. Moreover, it introduces QD-based sensors and highlights different sensing mechanisms of QDs in details. The chapter concludes with a discussion on new trends in QD-based sensor applications such as microfluidic systems and wearable QD sensor platforms and briefly touches upon the future perspectives of the QD-based sensing technology.