Odhiambo Ruth A, Aluoch Austin O, Njenga Lydia W, Kagwanja Stanley M, Wandiga Shem O, Wendt Ola F
University of Nairobi P. O. Box 30197 - 00100 Nairobi Kenya.
Lund University Box 124 Lund Sweden
RSC Adv. 2018 Jan 17;8(7):3663-3672. doi: 10.1039/c7ra13589k. eCollection 2018 Jan 16.
A series of complexes with oxathiacrown ethers appended to a [Ru(bpy)] moiety have been synthesized and characterised using H NMR, C NMR, IR, electronic absorption and emission spectroscopies, mass spectrometry and elemental analyses. The complexes exhibit strong MLCT luminescence bands in the range 608-611 nm and one reversible metal centred oxidation potential in the range 1.00-1.02 V. Their selectivity and sensitivity towards Hg, Cd and Pb metal ions have been investigated using electronic absorption, luminescence, cyclic and differential pulse voltammetry titrations. Their responses towards selected cations and anions have also been investigated using electronic absorption and luminescence. While the complexes are selective towards Hg and Cd ions, none of them is selective towards Pb ions. In particular, complex 2 gives a selective change in the UV/Vis absorbance with Hg making it possible to detect mercury down to a detection limit of 68 ppm. The binding constants and limits of detection of the complexes have been calculated, with values ranging from 4.37 to 5.38 and 1.4 × 10 to 6.8 × 10 for log and LOD respectively.
已合成了一系列在[Ru(bpy)]部分连接有氧杂硫杂冠醚的配合物，并通过氢核磁共振、碳核磁共振、红外光谱、电子吸收和发射光谱、质谱以及元素分析对其进行了表征。这些配合物在608 - 611 nm范围内呈现出较强的金属-配体电荷转移发光带，并且在1.00 - 1.02 V范围内有一个可逆的金属中心氧化电位。使用电子吸收、发光、循环伏安和差分脉冲伏安滴定法研究了它们对汞、镉和铅金属离子的选择性和灵敏度。还使用电子吸收和发光研究了它们对选定阳离子和阴离子的响应。虽然这些配合物对汞离子和镉离子具有选择性，但它们对铅离子均无选择性。特别是，配合物2与汞反应时在紫外/可见吸收光谱上有选择性变化，使得检测汞的下限可达68 ppm。已计算出这些配合物的结合常数和检测限，log 的值范围为4.37至5.38，检测限的值范围为1.4×10至6.8×10。
