Spectroscopic Studies on the Interaction of Metallic Ions with an Imidazolyl-Phenolic System

Author(s)

Orfao, Jr., Ronaldo Barros ; Alves, Jessica ; Bartoloni, Fernando Heering

• Document type: Journal article
• Source: Journal of Fluorescence; v. 26, n. 4, p. 1373-1380, JUL 2016.
• Web of Science Citations: 5

Abstract

A fluorescent imidazolyl-phenolic compound was applied on the detection of metallic species (Cu2+, Al3+, Cr3+ and Fe3+) in a CH3CN/H2O (95/5, v/v) media. The presence and concentration of these cations altered significantly the emission profile of the probe, mainly lowering the signal intensity at 466 nm, while a new emission band around 395 nm appeared (for the trivalent ions). These results were rationalized as a combination of collisional quenching (K-SV in the 10(3)-10(4) L mol(-1) range) and formation of a coordinated compound. The later disrupts the Excited State Intramolecular Proton Transfer that regulates the keto-enol tautomerism originally present on the free probe. Since the quenching efficiency and the obtained emission profiles are drastically different for Cu2+ and Fe3+ ions, this allows their differential recognition. (AU)

• FAPESP's process: 13/17332-6 - Kinetical study of a PCET process using the chemiluminescent peroxyoxalate reaction
• Grantee: Jessica Alves
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 14/05813-2 - Use of fluorophores containing phenolic and nitrogenated groups on metal detection by light emission
• Grantee: Ronaldo Barros Orfão Junior
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 12/13807-7 - New tools for the study of electron transfer reactions in PS II model systems
• Grantee: Fernando Heering Bartoloni
• Support Opportunities: Regular Research Grants