We have developed a reliable, sensitive, label-free and turn-on sensor for H2O2 and glucose based on the cleavage of ssDNA by ˙OH and the fluorescence enhancement effect when guanine-rich (G-rich) DNA sequences are in proximity to DNA–silver nanoclusters (DNA–Ag NCs). In addition, we have also proved that ˙OH is indeed produced in the sensing system by adding antioxidants.
