Rapid and Visual Detection of Al3+ Based on Supramolecular Self‐Assembly of a Water‐Soluble Perylene Diimide Derivative

Abstract Aluminum (Al) is widely used in food industry, but excessive absorption of Al 3+ causes many serious health problems. Therefore, it is of great significance to determine the specificity of Al 3+ . In this study, we designed and synthesized a water‐soluble perylene diimide derivative (PDI‐Phe) for monitoring Al 3+ rapidly and visually. Through absorption and emission spectroscopy techniques, we systematically explored the properties and mechanism of the sensor to Al 3+ . The limit of detection (LOD) of Al 3+ was as low as 6.54 nM. And with the existence of Al 3+ , electrostatic interaction and intermolecular π‐π stacking promoted the aggregation and fluorescence quenching of PDI‐Phe. Even in the presence of other analytes, PDI‐Phe still had excellent selectivity and sensitivity for Al 3+ detection. Besides, it also had the characteristics of low cost, good water solubility, excellent chemical and optical stability, and easy synthesis. Finally, this method can be further applied to tap water samples.