Naked Eye and Colorimetric Detection of Cyanide with a 1, 3‐Diethyl‐2‐thiobarbituric Acid Substituted Ferrocene Chemosensor. Issue 7 (11th February 2021)

• Record Type: Journal Article
• Authors: Babu, Balaji; Mack, John; Nyokong, Tebello
• Is Part Of: ChemistrySelect. Volume 6:Issue 7(2021)
• Page Start: 1448
• Page End: 1452
• Publication Date: 2021-02-11
• Subjects: Colorimetric -- Donor-acceptor systems -- Metallocenes -- Sensors -- TD-DFT; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.202100163
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: A 1, 3‐diethyl‐2‐thiobarbituric‐acid‐substituted ferrocene (FET ) has been evaluated for its cyanide sensing ability by UV‐visible absorption spectroscopy and other characterization methods. FET provides a ratiometric colorimetric chemosensor for the CN − anion detection in 1 : 1 DMSO/H2 O ( v/v ) solution. The addition of CN − results in an immediate color change from dark blue to pale orange that is visible to the naked eye. Mechanism studies and molecular modelling with TD‐DFT calculations demonstrate that nucleophilic addition of CN − to an electrophilic sp 2 ‐hybridized carbon atom blocks charge transfer from the ferrocene ring complex to the thiobarbituric acid moiety. The FET sensor exhibits excellent selectivity for CN − and a limit of detection of 0.2 μM. Abstract : The sensor properties of a thiobarbituric‐acid‐substituted ferrocene (FET ) are reported. FET exhibits a colorimetric response to CN − due to disruption of the π‐system with excellent selectivity in the presence of other common anions. The limit of detection for CN − is 0.2 μM in 1 : 1 DMSO/H2 O solution. Test strips prepared with Whatman‐filter paper provide an immediate naked eye response in aqueous solution.