Construction of novel π-bridged fluorescent probes for Fe²⁺ monitoring in living cells and foods

Fe²⁺ plays a crucial role in biological systems as an essential trace element in the body. Iron is absorbed by the body through food and Fe²⁺ is also an important component of living cells; therefore, quantitative testing of Fe²⁺ in food and in living cells is of great importance. This paper presents the development of a novel π-bridge EDOT-based N-oxide turn-on fluorescent probe, designated as FeE, for the detection of Fe²⁺. The probe has been shown to exhibit excellent sensitivity, a favorable linear relationship between fluorescence signal intensity and Fe²⁺ concentration, and an effective immunity to interference. The probe has low cytotoxicity and has been successfully used to detect Fe²⁺ in cells using laser confocal fluorescence microscopy. It is also possible to determine the presence of Fe²⁺ in animal blood, spinach, apple juice, red wine, mineral water and metal cans.

The Fe²⁺ responsive probe FeE can be prepared as a Fe²⁺ responsive test strip that can detect Fe²⁺ in food samples and exogenous and endogenous Fe²⁺ in cells.