Construction of a fluorescent probe for selectively detecting singlet oxygen with a high sensitivity and large concentration range based on a two-step cascade sensing reaction.

A novel fluorescent probe XQ-1 for selectively detecting 1O2 on the basis of a two-step cascade reaction has been rationally constructed. The probe responded to 1O2 not only showing a high sensitivity, but also displaying a large concentration range, which means that the probe can be used as a powerful tool to monitor the efficacy of PDT toward cancer and concurrently track the adverse effects on healthy cells.