and are strongly related to metabolic activities. The increase of the ROS concentration in
organisms can result in several diseases, such as cardiovascular diseases and cancer. The
concentration of ROS in biologically relevant conditions is typically as low as around tens of
micromolars to 100 μM H2O2, which makes it necessary to develop ultrasensitive ROS-
responsive systems. A general approach is reported here to fabricate an ultrasensitive ROS …