A novel pyrazole bearing imidazole frame as ratiometric fluorescent chemosensor for Al 3+ /Fe 3+ ions and its application in HeLa cell imaging.

New pyrazole bearing imidazole derivative was successfully synthesized and thoroughly characterized by various spectroanalytical techniques. The sensor DIBI shows a highly selective and sensitive fluorescent response with the addition of Al ³⁺ /Fe ³⁺ ions in acetonitrile-water mixture. The strong fluorescent molecule exhibits a notable ratiometric emissions at 462 nm and 470 nm for Al ³⁺ and Fe ³⁺ ions, respectively (λ _ex  = 280 nm). Job's plot studies conclude that the coordination between DIBI with Al ³⁺ /Fe ³⁺ was 1:1 binding stoichiometry. The limit of detection of DIBI with Al ³⁺ /Fe ³⁺ was calculated as 2.12 × 10 ^-7  M and 1.73 × 10 ^-6  M, respectively. The TD-DFT calculations further supported the photonics performances of the free probe and its complexes. The reversibility and reusability of the sensor molecule are studied using EDTA. The probe was used to track Al ³⁺ /Fe ³⁺ in cancer cells via fluorescence microscopy.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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