Quantum Dots: Fluorescent Probes in Medical Diagnostics

Quantum dots (QDs) are semiconductor nanocrystals (1–20 nm) that possess unique optical and electronic properties, making them highly effective fluorescent probes in the field of medical diagnostics. Unlike their bulk counterparts, their nanoscale dimensions confer distinct properties, enabling applications that were unattainable with conventional materials. QD nanostructures are particularly well-suited for molecular imaging, biomarker detection, and multiplexed diagnostics owing to their exceptional photostability, broad absorption, and narrow tunable emission wavelengths. Additional key features include uniform size, biocompatibility, high fluorescence intensity with resistance to quenching, water stability, and excellent dispersibility. This chapter explores fundamental concepts of QDs, including synthesis and applications in bioimaging, biomarker detection, and multiplexed diagnostic platforms, while analyzing challenges such as cytotoxicity, biocompatibility, and regulatory concerns. It highlights the transformative role of QDs in precision medicine, detailing their impact on diagnostics and design strategies and providing a comprehensive perspective on integrating QDs into medical practices.