Yang L, Li M, Ruan S, Xu X, Wang Z, Wang S. Highly efficient coumarin-derived colorimetric chemosensors for sensitive sensing of fluoride ions and their applications in logic circuits.
SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021;
255:119718. [PMID:
33774418 DOI:
10.1016/j.saa.2021.119718]
[Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 03/09/2021] [Accepted: 03/15/2021] [Indexed: 06/12/2023]
Abstract
In this study, three new compounds 6-substituted-3-acetylcoumarin 4-(2'-isocamphanyl)thiosemicarbazones (3a, 3b, and 3c) were facilely synthesized and employed as colorimetric chemosensors for fluoride ions. The recognition behaviors of receptors 3a, 3b, and 3c toward F- were investigated by using UV-vis absorption spectroscopy. Among them, the receptor 3c displayed more superior sensitivity and rapid response time toward F- with a swift naked-eye color change from colorless to purple, and its detection limit was as low as 6.3 × 10-7 M, and the binding constant was calculated to be 2.58 × 104 M-1. Furthermore, the interaction mechanism between the receptor 3c and F- was studied by 1H NMR, HRMS, and density functional theory (DFT) studies, suggesting that initial formation of a hydrogen-bonded host-guest complex and the subsequent deprotonation of receptor 3c upon the addition of excess F-, which was responsible for the remarkable changes in the absorption spectra of 3c. Besides, a combinatorial logic circuit of IMPLICATION and INHIBITION gates at the molecular level was fabricated using the reversibility of receptor 3c toward F- and Mg2+. Finally, the test strips coated with receptor 3c revealed a good sensitivity for F- in an aqueous medium. Apart from that, the excellent performance of receptor 3c for detecting F- was reconfirmed by grinding them with KBr powder.
Collapse