Semiconductor quantum dots in tumor research

Semiconductor quantum dots (QDs) have attractive optical characteristics such as broad excitation spectra, narrow emission spectra, long fluorescence lifetime and negligible optical bleaching. Due to these characteristics, QDs have many important roles in fluorescence imaging and labeling. In recent years, QDs have been widely used as biolabels and biosensors in tumor research. The useful photophysical and chemical properties of QDs make them strong candidates for use in early tumor diagnosis, prognosis, and monitoring. Besides, QDs have also been applied in tumor drug delivery systems and photodynamic therapy, so they are of considerable significance in tumor research. In this review, we introduce the optical properties of QDs and summarize their various applications in tumor research, especially in tumor imaging, tumor serum diagnosis, tumor drug delivery, and photodynamic therapy. Finally, conclusions are made by providing some critical challenges and prospects of QDs in tumor research.