Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Av. Fuentenueva s/n, 18071 Granada, Spain.
Analyst. 2013 Oct 21;138(20):6134-43. doi: 10.1039/c3an00064h.
A new europium(III) membrane luminescent sensor based on a new tridentate bis(phosphinic acid)phosphine oxide (3) system has been developed. The synthesis of this new ligand is described and its full characterization by NMR, IR and elemental analyses is provided. The luminescent complex formed between europium(III) chloride and ligand 3 was evaluated in solution, observing that its spectroscopic and chemical characteristics are excellent for measuring in polymer inclusion membranes. Included in a Nafion membrane, all the parameters (ligand and ionic additives) that can affect the sensitivity and selectivity of the sensing membrane as well as the instrumental conditions were carefully optimized. The best luminescence signal (λexc = 229.06 nm and λem = 616.02 nm) was exhibited by the sensing film having a Nafion : ligand composition of 262.3 : 0.6 mg mL(-1). The membrane sensor showed a short response time (t95 = 5.0 ± 0.2 min) and an optimum working pH of 5.0 (25 mM acetate buffer solution). The membrane sensor manifested a good selectivity toward europium(III) ions with respect to other trivalent metals (iron, chromium and aluminium) and lanthanide(III) ions (lanthanum, samarium, terbium and ytterbium), although a small positive interference of terbium(III) ions was observed. It provided a linear range from 1.9 × 10(-8) to 5.0 × 10(-6) M with a very low detection limit (5.8 × 10(-9) M) and sensitivity (8.57 × 10(-7) a.u. per M). The applicability of this sensing film has been demonstrated by analyzing different kinds of spiked water samples obtaining recovery percentages of 95-97%.
一种基于新型三齿双（膦酸）亚膦酸（3）配体的新型铕（III）膜荧光传感器已经开发出来。描述了该新配体的合成，并通过 NMR、IR 和元素分析提供了其全谱特征。在溶液中评估了铕（III）氯化物与配体 3 形成的发光络合物，观察到其光谱和化学特性非常适合于聚合物包容膜中的测量。将其包含在 Nafion 膜中，仔细优化了所有可能影响传感膜灵敏度和选择性的参数（配体和离子添加剂）以及仪器条件。具有 Nafion：配体组成比为 262.3：0.6 mg mL(-1)的传感膜表现出最佳的发光信号（λ exc= 229.06nm 和 λ em= 616.02nm）。该膜传感器具有较短的响应时间（t95 = 5.0 ± 0.2 min）和最佳工作 pH 值为 5.0（25 mM 醋酸缓冲溶液）。该膜传感器对铕（III）离子相对于其他三价金属（铁、铬和铝）和镧系（III）离子（镧、钐、铽和镱）表现出良好的选择性，尽管观察到三价铽（III）离子的轻微正干扰。它提供了从 1.9 × 10(-8)到 5.0 × 10(-6) M 的线性范围，具有非常低的检测限（5.8 × 10(-9) M）和灵敏度（8.57 × 10(-7) a.u. per M）。通过分析不同种类的加标水样，证明了这种传感膜的适用性，得到了 95-97%的回收率。
