A coumarin-based “turn-on” fluorescent sensor for the determination of Al3+: single crystal X-ray structure and cell staining properties

Abstract

An efficient Al(3+) receptor, 6-(2-hydroxybenzylideneamino)-2H-chromen-2-one (HBC), has been synthesized by condensing salicylaldehyde with 6-aminocoumarin. The molecular structure of HBC has been determined by a single crystal X-ray analysis. It was established that in the presence of Al(3+), HBC shows 25 fold enhancement of fluorescence intensity which might be attributed to the chelation-enhanced fluorescence (CHEF) process. HBC binds Al(NO3)3 in a 1 : 1 stoichiometry with a binding constant (K) of 7.9 × 10(4) M(-1). Fe(3+) and Mn(2+) quench the emission intensity of the [HBC + Al(3+)] system to an insignificant extent at a concentration 10 times higher compared to that of Al(3+). HBC is highly efficient in the detection of intracellular Al(3+) under a fluorescence microscope.

Bis-Schiff base as a donor–acceptor fluorescent probe: Recognition of Al3+ ions in near 100% aqueous solution

“…The interaction of HL and Al 3+ [47][48][49]. Of course, all of these were further confirmed by ESI-MS, 1 HNMR titration.…”

Cell permeable fluorescent colorimetric Schiff base chemoreceptor for detecting F− in aqueous solvent

“…In view of above we have planned to furthermore investigate the ability of PMP in detection of intracellular fluoride [31,[57][58][59][60][61]. For this study two types of cells viz.…”

Two Schiff-base fluorescent sensors for selective sensing of aluminum (III): Experimental and computational studies

“…In general, as a hard-acid, it has been found that Al 3+ prefers a coordination sphere containing N and O as hard-base donor sites, on the other hand, the Schiff-base could provide a nitrogen-oxygen-rich coordination environment for the hard-acid Al 3+ [23][24][25][26]. Therefore, it can be conceived that the Schiff-base would develop a fluorescent probe for detection of Al 3+ .…”