Selective detection of Al(3+) and citric acid with a fluorescent amphiphile.
An amphiphilic fluorescent dye with a disulfonated BODIPY head group and a heptadecyl side chain is described. In buffered aqueous solution, the amphiphile can form aggregates with a critical micelle concentration of ∼20 μM. The aggregation of the dye is associated with a strong quenching of its fluorescence. Al(3+) promotes aggregation, whereas other metal ions have a much smaller effect, in particular when histidine is added as masking agent. The Al(3+)-induced aggregation can be used to sense Al(3+) in the low micromolar concentration range with high selectivity. Furthermore, we demonstrate that a dye-Al(3+) mixture can be used as a sensing ensemble for the detection of citric acid. The assay allows quantifying the citric acid content of commercial beverages such as energy drinks.
Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland. kay.severin@epfl.ch.
Ziya
Z
Köstereli
Kay
K
Severin