A cell-compatible red light-emitting multianalyte chemosensor via three birds, one stone strategy

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 2021-01, Vol.404, p.112889, Article 112889
• Main Authors: Mabhai, Subhabrata, Dolai, Malay, Dey, Surya Kanta, Dhara, Anamika, Choudhury, Sujata Maiti, Das, Bhriguram, Dey, Satyajit, Jana, Atanu, Banerjee, Deb Ranjan
• Format: Article
• Language: English
• Subjects: Azobenzene; Chemosensor; Paramagnetic quenching; PET – CHEF; Rhodamine
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/j.jphotochem.2020.112889

[Display omitted] •A new PET – CHEF controlled rhodamine-azobenzene based chemosensor is reported.•Chemoselection of Cu2+, Al3+, and Cr3+ by UV–vis absorption study and Al3+ and Cr3+ by fluorimetric study.•The detection limit is as low as 1.1 × 10−6 M, 1.3 × 10−6 M, and 1.5 × 10−6 M for Cu2+, Al3+, and Cr3+ respectively.•The sensor is capable to mimic an AND LOGIC GATE and can be used as onsight solid probe (paper strip).•The sensor L is cell-permeable and is utilized to map the intracellular concentration of Al3+ and Cr3+ in HLCs. The design and synthesis of red light-emitting multianalyte chemosensors have always been a challenging task because of its specific requirement of coordination pocket and selective fluorescence mechanism. Herein, we develop a chemosensor via “three birds, one stone” strategy in which we can detect three metal ions with one ligand. A highly sensitive new azo functionalized rhodamine based luminescent sensor is synthesized for selective fluorogenic recognition of Al3+, Cr3+, and chromogenic recognition of Cu2+ in ethanol : H2O medium in the red light-emitting zone. Among the guest metals, Cu2+ efficiently quenches the emission whereas Al3+ and Cr3+ induce increased luminescent 4.76 fold for Al3+ and 2.47 fold for Cr3+ through chelation-enhanced fluorescence (CHEF) and photo-induced electron transfer (PET) regulated mechanism with the formation of 1:1 complex. The restricted imine isomerization through complex formation inhibits ongoing PET process with the instantaneous onset of CHEF. The mechanism is in good consonance with NMR (1H &13C), FT-IR, elemental analysis, DFT, TCSPC, and pH-dependent studies. Micromolar range detection of 1.1 μM, 1.3 μM, and 1.5 μM for Cu2+, Al3+, and Cr3+ respectively, easy penetration into HLCs cells and higher imaging resolution increase its potentiality to assess Al3+ and Cr3+ in vitro. Moreover, paper strip application increases its viability as an onsite naked-eye portable solid probe.