A Glutathione-Responsive Luminescence Sensor Based on Dual-Emissive Persistent Luminescent Nanoparticles for Ratiometric Tumor Imaging

Persistent luminescent nanoparticles (PLNP) have outstanding advantages in low-background imaging. However, avoiding exogenous interference and false positive signals to achieve precise imaging is still a problem. In addition, it is also a great challenge to intelligently control the size of PLNP. Herein, we report an intelligent luminescence ratiometric sensor based on ultra-small dual-emissive PLNP for precise tumor-targeted imaging. ZnGa₂O₄:Cr PLNP with a particle size of c.a. 5–10 nm and two emission peaks at 708 nm and 501 nm were firstly synthesized by thermal decomposition method along with systematical controlling the amount of chromium. [email protected] sensor was further constructed with a constant ratio (I₇₀₈/I₅₀₁) which is not interfered by exogenous factors such as detection time window and probe concentration. However, high concentrations of glutathione in the tumor microenvironment can specifically trigger the change of I₇₀₈/I₅₀₁ and cause the sensor to self-assemble into clusters at tumor site, thus realizing long-term retention and specificity imaging.