A density-controlled scaffolding strategy for covalent functionalization of carbon-fiber microelectrodes
A density-controlled scaffolding strategy for covalent functionalization of carbon-fiber microelectrodes
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DOI：
10.1039/c5ay00501a
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发表时间：
2015-08
影响因子：
3.1
通讯作者：
Yuanyuan Yang;A. Ibrahim;Jennifer L. Stockdill;P. Hashemi
中科院分区：
文献类型：
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作者：
Yuanyuan Yang;A. Ibrahim;Jennifer L. Stockdill;P. Hashemi
痕量金属检测在环境和生物系统中具有重要意义。开发一种便携式和灵敏的设备，可以真实的实时测定痕量金属的水平是至关重要的。最近，我们描述了一种超快速和灵敏的检测方法，在水环境样品中使用快速扫描循环伏安法（FSCV）在碳纤维微电极（CFMs）。然而，该技术应用于更复杂的样品受到分析选择性的限制。在本文中，我们描述了一个支架战略的共价修饰的CFMs作为一个平台，用于创建选择性的吸附位点。我们通过电化学还原炔基芳基重氮盐的承载空间差异的甲硅烷基基团，控制支架的密度，在CFMs上创建一个单层的乙炔封端的支架。脱甲硅烷基化揭示了通过Cu（I）催化的叠氮化物-炔环加成（CuAAC）进一步官能化的炔。作为原理证明，我们优化了叠氮甲基二茂铁与炔接枝的条件。电化学验证了CFMs的所有表面变化。这种创新的策略提供了一个广泛适用的方法来生成分析选择性CFM的基础。广义的方法提供了潜在的附加叠氮化物的识别基团以高通量的方式连接到不同的电极。该技术最终将允许对复杂生态和生物系统中的金属进行实时超选择性FSCV分析。
Trace metal detection is of great importance in environmental and biological systems. It is crucial to develop a portable and sensitive device that can determine levels of trace metals in real time. Recently, we described a method for ultrafast and sensitive detection of Cu(II) and Pb(II) in aqueous environmental samples using fast scan cyclic voltammetry (FSCV) at carbon-fiber microelectrodes (CFMs). However, the application of this technique to more complex samples is limited by analytical selectivity. In this paper, we describe a scaffolding strategy for covalent modification of CFMs as a platform for creating selective adsorption sites. We create a monolayer of acetylene-terminated scaffolds on CFMs through the electrochemical reduction of alkynyl aryl diazonium salts bearing sterically differentiated silyl groups, which control the density of the scaffolds. Desilylation reveals the alkyne for further functionalization via Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC). As a proof of principle, we optimized the conditions for azidomethyl ferrocene to be grafted with the alkynes. All the surface variations of CFMs are electrochemically verified. This innovative strategy provides the groundwork for a broadly applicable method to generate analyte-selective CFMs. The generalized approach offers the potential to attach azide-appended recognition groups to different electrodes in a high throughput manner. This technology will ultimately allow real-time ultra-selective FSCV analysis of metals in complex ecological and biological systems.