Orfão Ronaldo Barros, Alves Jessica, Bartoloni Fernando Heering
Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, Brazil.
J Fluoresc. 2016 Jul;26(4):1373-80. doi: 10.1007/s10895-016-1828-x. Epub 2016 May 23.
A fluorescent imidazolyl-phenolic compound was applied on the detection of metallic species (Cu(2+), Al(3+), Cr(3+) and Fe(3+)) 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 (KSV 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 Cu(2+) and Fe(3+) ions, this allows their differential recognition.
一种荧光咪唑基酚类化合物被用于在CH3CN/H2O（95/5，v/v）介质中检测金属离子（Cu(2+)、Al(3+)、Cr(3+)和Fe(3+)）。这些阳离子的存在和浓度显著改变了探针的发射光谱，主要是降低了466 nm处的信号强度，同时在395 nm左右出现了一个新的发射带（对于三价离子）。这些结果被解释为碰撞猝灭（KSV在10(3)-10(4) L mol(-1)范围内）和配位化合物形成的组合。后者破坏了调节游离探针上原本存在的酮-烯醇互变异构的激发态分子内质子转移。由于Cu(2+)和Fe(3+)离子的猝灭效率和获得的发射光谱有很大不同，这使得它们能够被差异性识别。
