Baker Brian R, Lai Rebecca Y, Wood McCall S, Doctor Elaine H, Heeger Alan J, Plaxco Kevin W
Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA.
J Am Chem Soc. 2006 Mar 15;128(10):3138-9. doi: 10.1021/ja056957p.
Whereas spectroscopic and chromatographic techniques for the detection of small organic molecules have achieved impressive results, these methods are generally slow and cumbersome, and thus the development of a general means for the real-time, electronic detection of such targets remains a compelling goal. Here we demonstrate a potentially general, label-free electronic method for the detection of small-molecule targets by building a rapid, reagentless biosensor for the detection of cocaine. The sensor, based on the electrochemical interrogation of a structure-switching aptamer, specifically detects micromolar cocaine in seconds. Because signal generation is based on binding-induced folding, the sensor is highly selective and works directly in blood serum and in the presence of commonly employed interferents and cutting agents, and because all of the sensor components are covalently attached to the electrode surface, the sensor is also reusable: we achieve >99% signal regeneration upon a brief, room temperature aqueous wash. Given recent advances in the generation of highly specific aptamers, this detection platform may be readily adapted for the detection of other small molecules of a wide range of clinically and environmentally relevant small molecules.
尽管用于检测小分子有机化合物的光谱和色谱技术已经取得了令人瞩目的成果，但这些方法通常操作缓慢且繁琐，因此开发一种用于实时、电子检测此类目标的通用方法仍然是一个迫切的目标。在此，我们通过构建一种用于检测可卡因的快速、无需试剂的生物传感器，展示了一种潜在通用的、无标记的电子方法来检测小分子目标。该传感器基于对结构转换适配体的电化学检测，能在数秒内特异性检测出微摩尔浓度的可卡因。由于信号产生基于结合诱导的折叠，该传感器具有高度选择性，可直接在血清中以及存在常用干扰物和切割剂的情况下工作，并且由于所有传感器组件都共价连接到电极表面，该传感器还可重复使用：在室温下进行简短的水洗后，我们实现了>99%的信号再生。鉴于在生成高度特异性适配体方面的最新进展，该检测平台可能很容易适用于检测其他广泛的临床和环境相关小分子。
