Ultrafast and nanomolar detection of Al3+: Furazan based fluorescent chemosensor and its practices in Smartphone, test kit, water samples and living–cell

[Display omitted] •A new fluorescent chemosensor (SDAF) was developed for Al3+.•The SDAF has an ultralow detection limit (28 nM) and fast response time.•DFT studies were strongly confirmed the spectroscopy results.•The SDAF was successfully used to detect Al3+ in water samples, test-kits and living cells. A new fluorescent chemoprobe (SDAF) was successfully synthesized and utilized as a sensor for the recognition of Al3+ in EtOH:HEPES (3:2, v:v, pH: 7.0) media. The SDAF depicted a selective “turn–on” response at λem = 467 nm to Al3+ over competitive cations, and the SDAF–Al3+ complex had a reversible response with F−. The limit of detection (LOD) was found about at nano–molar level (28.0 nM), demonstrating the sensitivity of the chemoprobe toward Al3+. The binding stoichiometry of SDAF–Al3+ was investigated by TOF–MS, Job's plot, 1H NMR and 13C NMR methods and found as 1:1. The recognition mechanisms of SDAF for the detection of Al3+ were the –C = N isomerization and photoinduced electron transfer (PET) mechanisms, and they were confirmed by density functional theory (DFT) computation. Furthermore, the SDAF was successfully employed in living–cell bioimaging and cytotoxicity, it was also utilized in Smartphone, test–kit and natural spring water (recovery values; 89.01 %– 96.33 %)applications.