Quadruple-channel sensing: a molecular sensor with a single type of receptor site for selective and quantitative multi-ion analysis.
Quadruple-channel sensing: a molecular sensor with a single type of receptor site for selective and quantitative multi-ion analysis.
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DOI：
10.1002/anie.200603362
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发表时间：
2007-01
影响因子：
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通讯作者：
M. Schmittel;Hengwei Lin
中科院分区：
文献类型：
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作者：
M. Schmittel;Hengwei Lin
高选择性阳离子或阴离子传感对于许多技术领域都是必不可少的，包括环境、生物、临床和废物管理应用。[1]对于重金属和过渡金属离子（如Pb 2+，Cd 2+和Hg 2 +; Cu 2+和Fe 3+），由于其高毒性和在生物系统中的关键作用，选择性感觉方案特别重要。[2]虽然金属离子传感的各种概念已经被安装以提高灵敏度，选择性和动态工作范围[3]，但化学物种[4]和多分析物混合物的聚集体的识别仍然是一个重大挑战。[5]在这种情况下，一个“实验室的分子”的同时，虽然只有定性，检测Zn 2+，H+和Na+的逻辑门的方法最近已经被描述。[4]然而，即使是这种创新的方法也遵循了仍然主导传统传感器设计的范式：一个受体位点对应一种分析物。作为一种替代策略，我们和其他人[6]研究了一种传感器分子，该分子通过使用一系列检测方法对单一类型的受体单元进行多离子分析。为了在各种传感通道中获得不同的金属离子选择性，受体（在我们的情况下为氮杂冠醚）应根据检测方法表现出不同的构象偏好。该特征可以通过附近的空间邻接来实现，其防止氮杂冠醚位点和用于光谱研究的π系统的完美重叠。根据重叠和传感方法，氮杂冠醚环对空间邻接的压缩可能因此调节受体的可用构象空间（参见支持信息中的图S8）。到目前为止，很少研究结合位点的空间扰动和构象约束[3d，7]，如果是这样，那么大多数情况下只有一种光谱技术[8]，从而排除了用不同的检测方法检测不同的选择性。为了探索上述概念的有用性，我们将注意力转向钌三（二亚胺）络合物，因为它们的UV/维斯，光致发光（PL），电致化学发光（ECL）[9]和氧化还原特性已经在化学传感器领域得到很好的建立[10]，尽管从未在四通道传感装置中（图1）。[9，11]作为测试案例，以氮杂冠醚为受体单元的配合物1被设计并从相应的菲-N-（2-甲基-2-苯基）-2-甲基-N-（2-甲基-2-苯基）-3-甲基-N-（2-甲基-2-苯基）-
Highly selective cation or anion sensing is imperative for many areas of technology, including environmental, biological, clinical, and waste management applications.[1] For heavy-and transition-metal ions (eg Pb2+, Cd2+, and Hg2+; Cu2+ and Fe3+), selective sensory protocols are particularly critical owing to their high toxicity and crucial role in biological systems.[2] Although various concepts in metal-ion sensing have been installed to enhance sensitivity, selectivity, and the dynamic working range,[3] the recognition of congregations of chemical species [4] and of multianalyte mixtures still poses a major challenge.[5] In this context, a “lab on a molecule” for the simultaneous, although only qualitative, detection of Zn2+, H+, and Na+ by a logic-gate approach has recently been described.[4] However, even this innovative approach follows the paradigm that is still dominating traditional sensor design: one receptor site for one analyte. As an alternative strategy, we and others [6] investigated a sensor molecule that operates on a single type of receptor unit for multi-ion analysis by using an array of detection methods. To obtain different metal-ion selectivities in the various sensing channels, the receptor, in our case an aza crown ether, should exhibit disparate conformational preferences depending on the detection method. This feature may be implemented by a nearby steric abutment, which prevents perfect overlap of the aza crown ether site and the π system used for spectroscopic investigation. Depending on the overlap and thus on the sensing method, compression of the aza crown ether ring against the steric abutment may thus modulate the available conformational space of the receptor (see Figure S8 in the Supporting Information). So far, steric perturbations and conformational constraints at binding sites have rarely been investigated [3d, 7] and if so, then mostly with only one spectroscopic technique [8] thus precluding detection of different selectivities with distinct detection methods.To explore the usefulness of the above concept, we turned our attention to ruthenium tris (diimine) complexes as their UV/Vis, photoluminescence (PL), electrogenerated chemiluminescence (ECL),[9] and redox properties are already well established [10] in the field of chemosensors, although never in a quadruple-channel sensing setup (Figure 1).[9, 11] As a test case, complex 1 with aza crown ethers as the receptor units was designed and prepared from the corresponding phenan-