Development of Near Infrared-Fluorescent Nanophosphors and Applications for Cancer Diagnosis and Therapy

Figure 1

Advantage of NIR-NIR imaging system. Near infrared (NIR) emission by NIR excitation is observed using a NIR-NIR system. Due to weaker scattering and absorption, NIR light can penetrate deeper into/from tissues. In contrast, excitation light in the visible (VIS) region cannot reach the imaging target in tissues in the conventional VIS-VIS imaging. In upconversion (NIR-VIS) imaging, although NIR excitation light can reach its target in tissues, only a weak VIS emission can be obtained.