A new turn-on benzimidazole-based greenish-yellow fluorescent sensor for Zn2+ ions at biological pH applicable in cell imaging. (4th July 2017)

• Record Type: Journal Article
• Authors: Maji, Abhishek; Pal, Siddhartha; Lohar, Somenath; Mukhopadhyay, Subhra Kanti; Chattopadhyay, Pabitra
• Is Part Of: New journal of chemistry. Volume 41:Number 15(2017)
• Page Start: 7583
• Page End: 7590
• Publication Date: 2017-07-04
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c7nj01821e
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : A newly designed and structurally characterized non-cytotoxic benzimidazole containing quinazoline derivative (HL ) acts as a 'turn-on' greenish-yellow fluorescent sensor selective for Zn 2+ ions at as low as 39.91 nM in 5 mM HEPES buffer (DMSO/water: 1/5, v/v) at biological pH. Abstract : A newly designed and structurally characterized benzimidazole containing compound, 2, 4-di- tert -butyl-6-(5, 6-dihydro benzo[4, 5] imidazo [1, 2- c ] quinazolin-6-yl)-phenol) (HL ), behaves as a 'turn-on' fluorescent sensor selective for Zn 2+ ions at as low as 39.91 nM within a very short responsive time (15–20 s) in 5 mM HEPES buffer (DMSO/water: 1/5, v/v) at biological pH. Thorough experimental and theoretical (DFT) studies indicate the occurrence of greenish yellow fluorescence through a chelation enhanced fluorescence (CHEF) process. Using this organic moiety (HL ) as a probe, almost no interference of other competitive ions in the detection of Zn 2+ ions was observed. The reaction ofHL with Zn 2+ led to the in situ formation of a tridentate monobasic ligand (HL 1 ) to produce the complex as[Zn(L 1 )2 ] through a [1, 5] sigmatropic-type shift ofHL prior to metal coordination.HL is also capable of detecting the intercellular distribution of Zn 2+ ions in Candida sp. cells under a fluorescence microscope by developing the image.