Significance: Hydrogen peroxide (H2O2) is a powerful effector of redox signaling. It is able to oxidize cysteine residues, metal ion centers, and lipids. Understanding H2O2-mediated signaling requires, to some extent, measurement of H2O2 level. Recent Advances: Chemically and genetically encoded fluorescent probes for the detection of H2O2 are currently the most sensitive and popular. Novel probes are constantly being developed, with the latest progress particular with boronates and genetically encoded probes.
Critical issues: All currently available probes display limitations in terms of sensitivity, local and temporal resolution, and specificity in the detection of low H2O2 concentrations. In this review, we discuss the power of fluorescent probes and the systems in which they have been successfully employed. Moreover, we recommend approaches for overcoming probe limitations and for the avoidance of artifacts.
Future directions: Constant improvements will lead to the generation of probes that are not only more sensitive but also specifically tailored to individual cellular compartments. Antioxid. Redox Signal. 29, 585-602.
Keywords: detection; detection probes; reactive oxygen species.