Engineering a dual-responsive, exosome-surface anchored DNA nanosensor for microenvironment monitoring in vivo

We propose an azoreductase and pH dual-responsive amphiphilic pyramidal tetrahedral DNA probe to construct a circulating exosome-surface anchored nanosensor for microenvironment monitoring in vivo. Based on the shuttle behavior, biocompatibility of the exosomes, and easy synthesis and modification of nucleic acids, both in vitro and in vivo results demonstrate that this nanosensor has excellent performance for activatable O₂ and pH imaging, and thus can distinguish disease areas from normal tissue areas. We expect it to be a useful tool for obtaining early abnormal fluctuations in the microenvironment, which is of great significance for the early detection of diseases.