A naphthalene based chemosensor for dual channel recognition of Al3+and relay recognition of Fe3+ in water-bearing system and bioimaging in zebrafish.

• A novel naphthalene based chemosensor SN was efficiently synthesized by one-step method, which can rapidly recognize Al3+by colorimetry and fluorescence dual channel and further continuously detect Fe3+in DMSO/H 2 O (9:1, V/V) with excellent selectivity and sensitivity. • The binding modes of SN to Al3+ and [ SN + Al3+] to Fe3+ were revealed by 1H NMR titration, HRMS, DFT and TD-DFT. • The SN and [ SN + Al3+] have been successfully used to identify Al3+ and Fe3+ in zebrafish organisms. A simple and rapidly responsive novel chemosensor SN (4-(((2-hydroxynaphthalen-1-yl)methylene)amino)-N-(pyrimidine-2-yl)benzenesulfonamide) was designed and synthesized using 2‑hydroxy‑1-naphthaldehyde as a fluorescent group and its structure was characterized by 1H NMR, 13C NMR and HRMS. Upon addition of only Al3+ in a mixed solvent system (DMSO/H 2 O, V/ V = 9:1), significant changes in UV–visible and fluorescence spectra were observed. At the same time, the solution exhibited noticeable color changes (from yellow to colorless) and fluorescence responses (from no fluorescence to blue fluorescence). The fluorescence chemosensor SN demonstrated excellent selectivity and sensitivity towards Al3+ with detection limits (LOD) of 1.174 × 10−8 M. Therefore, the SN chemosensor enables rapid and efficient detection of trace amounts of Al3+ in both environmental and biological settings through colorimetric and dual-channel fluorescence responses. Furthermore, under the same conditions, the in-situ generated [ SN + Al3+] system was used for relay detection of Fe3+ without the need for further optimization, purification, or separation steps. The experimental results showed that the addition of Fe3+ led to fluorescence quenching, eliminating interference from Al3+ during Fe3+ detection, and the detection limit was 1.85×10−8 M. In addition, the binding and sensing mechanism of chemosensor SN to Al3+ and [ SN + Al3+] to Fe3+were described in detail by 1H NMR titration experiment, HRMS, density functional theory (DFT) calculation and time-dependent density functional theory (TD-DFT). A novel chemical sensor SN based on naphthalene derivative was efficiently synthesized by one-step method, which can rapidly recognize Al3+by colorimetry and fluorescence dual channel and further continuously detect Fe3+in DMSO/H 2 O (V/ V = 9:1), which has excellent anti-interference and specific recognition ability. At the same time, the LOD of the sensor SN to Al3+ and [ SN + Al3+] to Fe3+ can reach 1.174 × 10−8 M and 1.85 × 10−8 M. In addition, based on job's plot experiments, 1H NMR titrations and HR-MS analyses, a plausible mechanism for the interaction of the sensor SN with Al3+ and [ SN + Al3+] with Fe3+ was proposed, and the above-mentioned sensing mechanism was further confirmed by DFT calculation. Meanwhile, the sensor SN and in situ generation [ SN + Al3+] have been successfully applied for the detection of Al3+ and Fe3+ in zebrafish organisms. [Display omitted] [ABSTRACT FROM AUTHOR]