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

Graphical A water-soluble PDI, N, N′ -bis (L-phenylalanine)-3,4,9,10-perylene tetracarboxylic diimide (PDI-Phe) is designed and synthesized for rapid and selective fluorescent detection of Al 3+ in aqueous solution. In the presence of Al 3+ , non-covalent interactions such as electrostatic and π-π interactions would promote supramolecular self-assembly between PDI-Phe and Al 3+ , making the aggregation and fluorescence quenching of PDI-Phe, thereby realizing the quantitative detection of Al3+ between 100 nM and 900 nM. The limit of detection (LOD) of Al 3+ was as low as 6.54 nM. 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.