Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic.
Molecules. 2020 Sep 11;25(18):4164. doi: 10.3390/molecules25184164.
Ln(III) complexes of macrocyclic ligands are used in medicinal chemistry, for example as contrast agents in MRI or radiopharmaceutical compounds, and in diagnostics using fluorescence imaging. This paper is devoted to a spectroscopic study of Ln(III) ternary complexes consisting of macrocyclic heptadentate DO3A and bidentate 3-isoquinolinate (IQCA) ligands. IQCA serves as an efficient antenna ligand, leading to a higher quantum yield and Stokes shift (250-350 nm for Eu, Tb, Sm, Dy in VIS region, 550-650 nm for Yb, Nd in NIR region). The shielding-quenching effect of NAD(P)H on the luminescence of the Ln(III) ternary complexes was investigated in detail and this phenomenon was utilized for the analytical determination of this compound. This general approach was verified through an enzymatic reaction during which the course of ethanol transformation catalyzed by alcohol-dehydrogenase (ADH) was followed by luminescence spectroscopy. This method can be utilized for selective and sensitive determination of ethanol concentration and/or ADH enzyme activity. This new analytical method can also be used for other enzyme systems coupled with NAD(P)H/NAD(P) redox pairs.
Ln(III)配合物被广泛应用于医学化学领域，例如作为磁共振成像（MRI）中的造影剂或放射性药物化合物，以及荧光成像诊断中。本文致力于研究由大环七齿 DO3A 和双齿 3-异喹啉甲酸（IQCA）配体组成的 Ln(III)三元配合物的光谱性质。IQCA 作为一种高效的天线配体，可提高量子产率和斯托克斯位移（Eu、Tb、Sm、Dy 在可见区的范围为 250-350nm，Yb、Nd 在近红外区的范围为 550-650nm）。详细研究了 NAD(P)H 对 Ln(III)三元配合物发光的屏蔽猝灭效应，并利用该现象对该化合物进行了分析测定。通过酶反应验证了这种通用方法，通过该方法通过荧光光谱法跟踪醇脱氢酶（ADH）催化的乙醇转化过程。该方法可用于选择性和灵敏地测定乙醇浓度和/或 ADH 酶活性。这种新的分析方法也可用于与 NAD(P)H/NAD(P)氧化还原对偶联的其他酶系统。
