Dual-channel recognition of Al3+ and Cu2+ ions using a chiral pyrene-based fluorescent sensor

Specific recognition between Al3+ and Cu2+ has been achieved based on the new mechanism of Cu2+ detection by pyrene dimerization.

Theoretical Design of Near-Infrared Al3+ Fluorescent Probes Based on Salicylaldehyde Acylhydrazone Schiff Base Derivatives

The aim of this paper is to design near-infrared (NIR) Al³⁺ fluorescent probes based on a Schiff base to extend their applications in biological systems. By combining benzo[h]quinoline unit and salicylaldehyde acylhydrazone, we designed two new Schiff base derivatives. According to theoretical simulations on previous experimental Al³⁺ probes, we obtained the appropriate theoretical approaches to describe the properties of these fluorescent probes. By employing such approaches on our newly designed molecules, it is found that the new molecules have high selectivity toward Al³⁺ and that their corresponding Al³⁺ complexes can emit NIR fluorescence. As a result, they are expected to be potential NIR Al³⁺ fluorescent probes.

Two new isomerous fluorescent chemosensors for Al(3+) based on photoinduced electron transfer

Two new isomerous PET fluorescent chemosensors (L and L') for Al(3+) have been designed, synthesized and characterized. The two chemosensors exhibited fluorescence enhancement upon binding Al(3+) in CH3CN by PET inhibition processes from both the sulfur and the nitrogen donors to anthracene. The job's plot, Benesi-Hildebrand plot and (1)H NMR titration experiments indicate that both chemosensors form a 1:1 complex with Al(3+). The binding constants were calculated to be (1.432±0.186)×10(5) and (1.427±0.970)×10(5), respectively. Furthermore, the lowest detection limit for Al(3+) in CH3CN was determined to be 4.8×10(-7)M and 2.2×10(-7)M, respectively.

Multifunctional Fe₃O₄ nanoparticles for highly sensitive detection and removal of Al(III) in aqueous solution

Fe(3)O(4) nanoparticles (NPs) decorated with rhodamine 6G Schiff base, which exhibit high selectivity and sensitivity toward Al(3+) over other common metal ions in aqueous media under a physiological pH window via a 1:1 binding mode, have been synthesized and characterized. The resulting conjugate renders the rhodamine 6G Schiff base unit more water soluble, and the detection limit reaches 0.3 ppb in water. Moreover, can detect Al(3+) in a wide pH span (5.0-11.0) and enrich/remove excess Al(3+) in water via an external magnetic field, which indicates that it has more potential and further practical applications for biology and toxicology. Furthermore, provides good fluorescent imaging of Al(3+) in living cells.

Highly selective and sensitive fluorescent turn-on chemosensor for Al3+ based on a novel photoinduced electron transfer approach

A photoinduced electron transfer (PET)-based chemosensor possessing dual PET processes by simultaneously introducing both nitrogen and sulfur donors was achieved. The fluorescence signal of the free chemosensor is in a normal-off state due to the sulfur donor being insensitive to environmental pH stimuli. As a result, the device can be used over a wide pH span of 3-11. Upon binding Al(3+), a significant fluorescence enhancement with a turn-on ratio over 110-fold was triggered by the inhibition of PET processes from both the sulfur and the nitrogen donors to the fluorophore.