A colorimetric and fluorescent chemosensor for selective detection of Cu²⁺ based on a new diarylethene with a benzophenone hydrazone unit

Abstract

A new photochromic diarylethene based on benzophenone hydrazone has been synthesized. Its photochromic and fluorescent properties changed upon alternating irradiation with UV/Vis light and adding Cu /EDTA in methanol, which showed that the diarylethene could be served as a colorimetric and fluorescent chemosensor for selective detection of Cu based on internal charge transfer processes. The colorimetric and turn-off fluorescent selective detection of Cu was attributed to the 2:1 complex of the diarylethene and Cu . The binding constant (Ka) was 1.53 × 10 L mol and the limit of detection of the diarylethene for Cu was calculated to be 1.45 × 10 mol L . In addition, the metal-responsive photochromic behavior of diarylethene was applied successfully to the construction of a molecular logic circuit.

Recent Advances in Photoswitchable Fluorescent and Colorimetric Probes

“…Photochromic molecules have received significant attention for Cu 2+ detection, with probes generally based on photochromic diarylethene. These probes operate via two main mechanisms: (1) coupling diarylethene with oxygen-containing aromatic dyes like fluorescein or rhodamine, where Cu 2+ induces the opening of the dye’s spirocyclic ring, enhancing fluorescence [ 137 , 138 ], and (2) linking diarylethene with specific ligands to create photo-controlled fluorescent probes where copper coordination changes the probe’s fluorescent properties [ 139 , 140 , 141 , 142 ].…”

Comparative study of 4-((4-aminophenyl)diazenyl)-2-((2-phenylhydrazono)methyl)phenol and N-(4-((4-hydroxy-3-((2-phenylhydrazono)methyl)phenyl)diazenyl)phenyl)acetamide - DFT method

“…The effect of pH on the azohydra-zone tautomerism of the ligand has been studied with UV-vis spectroscopy. Two types of complexes were obtained by reaction of the ligand with copper sulphatepentahydrate in methanol under different experimental conditions [9]. In the case of polymorphism, different structures melt into the same liquid.…”

A simple fluorescent switch with four states based on benzothiazole-spiropyran for reversible multicolor displays and anti-counterfeiting

“…In general, most of the FMSs were achieved by linking individual switches to other fluorophores with covalent or non-covalent bonds (Scheme 1a), which led to the remarkable development of many luminescence switches showing distinctive emission characteristics. [24][25][26][27][28][29] However, switching motifs with fewer and simpler units are more beneficial and plausible from the point of view of atomic efficiency. [30][31][32] Therefore, FMSs by fusing a single switch to a fluorophore through a shared central unit were designed, which was an effective and efficient method to construct FMSs with both emission color change and on/off switching (Scheme 1b).…”