Fluorogenic Probes for Intracellular Iron Detection

Iron is a crucial element required to sustain multiple biological processes, including oxygen transport, DNA synthesis, and electron transport. In living cells, iron exists as either ferrous iron (Fe²⁺) or ferric iron (Fe³⁺), and its redox forms are regulated by the labile iron pool. Both iron deficiency and excess can lead to a range of pathological conditions, such as anemia, cancer, neurodegenerative disorders, and ischemia and reperfusion injury. Iron overload can cause oxidative damage and even cell death, especially via ferroptosis. Impaired ferroptosis pathways are implicated in the pathogenesis of various diseases and are becoming attractive therapeutic targets. Therefore, developing methods to analyze dynamic iron changes in cells is crucial. In this chapter, we introduce several protocols that use fluorogenic iron probes (e.g., FerroFarRed, Calcein-AM, and FRET iron probe 1) to measure intracellular iron content.