Selective Fluorescent Sensing for Iron in Aqueous Solution by A Novel Functionalized Pillar[5]arene

Iron ion is one of the most physiologically important elements in metabolic processes, indispensable for all living systems. Since its excess can lead to severe diseases, new approaches for its monitoring in water samples are urgently needed to meet requirements. Here, we firstly report a novel and universal route for the synthesis of a series of pillar[n]arene derivates containing one benzoquinone unit by photocatalysis. With this in hand, an anthracene - appended water - soluble pillar[5]arene (H) with excellent fluorescence sensing potency was prepared. H enabled the ultrasensitive detection of iron ions in aqueous solution with limits of detection of 10^-8  M. Over a wide range of metal ions, H exhibited specific selectivity toward Fe³⁺ . More importantly, H could still properly operate in a simulated sewage sample, coexisting with multiple interference ions.