A New Aptameric Biosensor for Cocaine Based on Surface-Enhanced Raman Scattering Spectroscopy
A New Aptameric Biosensor for Cocaine Based on Surface-Enhanced Raman Scattering Spectroscopy
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DOI：
10.1002/chem.200701307
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发表时间：
2008-01-01
影响因子：
4.3
通讯作者：
Yu, Ruqin
中科院分区：
文献类型：
--
作者：
Chen, Jiwei;Jiang, Jianhui;Yu, Ruqin
本研究报告的原理证明的无试剂适配体传感器的基础上，表面增强拉曼散射（Sers）光谱与“信号”架构使用模型目标的可卡因。这种新的适体传感器是基于结合靶上的表面束缚的适体的构象变化，其将特定的拉曼报告分子吸引到Sers基底附近，从而由于Sers的局部增强效应而增加了拉曼散射信号。为了提高传感器的响应性能，该传感器是由可卡因为模板的3 '-末端四甲基罗丹明（TMR）标记的DNA适配体通过在5'末端的烷基乙氧基部分在银胶体膜上的混合自组装而制成的。这种固定策略优化了适体在表面上的取向，并促进了在结合靶标上的折叠。在优化的测定条件下，可以确定可卡因的浓度为1 μ M，这与类似的适配体传感器的基础上，电化学和荧光技术相比较有利。传感器可以通过用缓冲液洗涤而容易地再生。这些结果表明，基于SERS的传感器可能会创造一个新的维度，为未来的发展，适配体传感器的灵敏测定在生物化学和生物医学研究。
The present study reports the proof of principle of a reagentless aptameric sensor based on surface-enhanced Raman scattering (SERS) spectroscopy with "signal-on" architecture using a model target of cocaine. This new aptameric sensor is based on the conformational change of the surface-tethered aptamer on a binding target that draws a certain Raman reporter in close proximity to the SERS substrate, thereby increasing the Raman scattering signal due to the local enhancement effect of SERS. To improve the response performance, the sensor is fabricated from a cocaine-templated mixed self-assembly of a 3'-terminal tetramethylrhodamine (TMR)-labeled DNA aptamer oil a silver colloid film by means of an alkanethiol moiety at the 5' end. This immobilization strategy optimizes the orientation of the aptamer on the surface and facilitates the folding on the binding target. Under optimized assay conditions, one can determine cocaine at a concentration of 1 mu M, which compares favorably with analogous aptameric sensors based on electrochemical and fluorescence techniques. The sensor can be readily regenerated by being washed with a buffer. These results suggest that the SERS-based transducer might create a new dimension for future development of aptameric sensors for sensitive determination in biochemical and biomedical studies.