A new use for an old molecule: N-phenyl-2-(2-hydroxynaphthalen-1-ylmethylene)hydrazinecarbothioamide as a ratiometric ‘Off–On’ fluorescent probe for iron

• DOI: 10.1016/j.tetlet.2011.11.126
• Publication Date: 2011-12-07T18:57:28Z
• Authors: María José Casanu...; Colin Fowley; Barry W. Hyland; Graham R.C. Hamilton; Dolores Galindo-R...; John F. Callan
• Keywords: Ratiometric; Iron(III); 01 natural sciences; Fluorescence; Sensor; 0104 chemical sciences

N-Phenyl-2-(2-hydroxynaphthalen-1-ylmethylene)hydrazinecarbothioamide has been investigated as a fluorescent sensor for the determination of Fe(III) in aqueous solutions. The probe was prepared by the facile Schiff base condensation of 2-hydroxy-1-napthaldehyde with N-phenylhydrazinecarbothioamide. The sensor displayed good selectivity for Fe(III) when tested against a range of biologically and environmentally important cations. A concentration dependent increase in the emission of two fluorescent bands at 425 and 495 nm was observed upon increasing Fe(III) addition resulting in a linear ratiometric response in the 17-37 mu M range. The binding stoichiometry was confirmed as 1:1 (host/guest) with the binding constant (log beta) calculated as 4.56. (C) 2011 Elsevier Ltd. All rights reserved.