A Facile Preparation of a New Water-Soluble Acridine Derivative and Application as a Turn-off Fluorescence Chemosensor for Selective Detection of Hg2

• Published in: Journal of fluorescence Vol. 30; no. 2; pp. 235 - 247
• Main Authors: Nunes, Marcelo Carpes, dos Santos Carlos, Fabiane, Fuganti, Otávio, da Silva, Letícia Aparecida, Ribas, Hennrique Taborda, Winnischofer, Sheila Maria Brochado, Nunes, Fábio Souza
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.03.2020; Springer Nature B.V
• Subjects: Analytical Chemistry; Aqueous solutions; Biochemistry; Biological and Medical Physics; Biomedical and Life Sciences; Biomedicine; Biophysics; Biotechnology; Chemical sensors; Chemoreceptors; Distilled water; Fluorescence; Least squares method; Mathematical analysis; Mercury (metal); Original Article; Sensors; DFT; Mercury(II); Fluorescent chemosensor; 4,5-Bis (thiolmethyl)acridine; Supramolecular chemistry
• ISSN: 1053-0509; 1573-4994
• DOI: 10.1007/s10895-020-02489-z

A new acridine-based chemosensor was prepared, characterized and investigated for quantitative detection of Hg 2+ ions in aqueous solutions. DFT and TD-DFT calculations showed that formation of a coordination bond between Hg 2+ and the thiolate-sensor accounts for the fluorescence quenching, forming [HgL S Cl 2 ] 2− as the most stable species. Limit of detection and limit of quantification were as low as 4.40 and 14.7 μmol L −1 , respectively (R 2  = 0.9892, least squares method), and a linear concentration range of 14.7–100 μmol L −1 . Benesi-Hildebrand and Job formalisms are in accordance with the formation of a stable complex with a 1:1 (metal ion/sensor) ratio, and a determined binding constant of 5.14 × 10 3 L mol −1 . Robustness was verified based on the variation of several analytical conditions. In addition, the method presented maximum relative standard deviation of 4.6%, and recovery results was (90.3 ± 4,6)% from distilled water, with no effect of interfering ions. Analytical figures of merit showed that the sensor can be an attractive low cost alternative for detection of Hg 2+ .