Abstract：
Nucleic-acid aptamers consisting in single-stranded DNA oligonucleotides emerged as very promising biorecognition elements for electrochemical biosensors applied in various fields such as medicine, environmental, and food safety. Despite their outstanding features, such as high-binding affinity for a broad range of targets, high stability, low cost and ease of modification, numerous challenges had to be overcome from the aptamer selection process on the design of functioning biosensing devices. Moreover, in the case of small molecules such as metabolites, toxins, drugs, etc., obtaining efficient binding aptamer sequences proved a challenging task given their small molecular surface and limited interactions between their functional groups and aptamer sequences. Thus, establishing consistent evaluation standards for aptamer affinity is crucial for the success of these aptamers in biosensing applications. In this context, this article will give an overview on the thermodynamic and structural aspects of the aptamer-target interaction, its specificity and selectivity, and will also highlight the current methods employed for determining the aptamer-binding affinity and the structural characterization of the aptamer-target complex. The critical aspects regarding the generation of aptamer-modified electrodes suitable for electrochemical sensing, such as appropriate bioreceptor immobilization strategy and experimental conditions which facilitate a convenient anchoring and stability of the aptamer, are also discussed. The review also summarizes some effective small molecule aptasensing platforms from the recent literature.
摘要：
由单链DNA寡核苷酸组成的核酸适体成为非常有前途的生物识别元件，用于电化学生物传感器，应用于医学等各个领域。环境,和食品安全。尽管其突出的特点，例如对广泛靶标的高结合亲和力，高稳定性,成本低，易于修改，许多挑战必须从适体选择过程中克服功能生物传感装置的设计。此外，在小分子如代谢物的情况下，毒素,毒品,等。,鉴于它们的小分子表面以及它们的官能团和适体序列之间有限的相互作用，获得有效的结合适体序列被证明是一项具有挑战性的任务。因此，建立一致的适体亲和力评估标准对于这些适体在生物传感应用中的成功至关重要。在这种情况下，本文将对适体-靶相互作用的热力学和结构方面进行概述，它的特异性和选择性，并且还将强调用于确定适体结合亲和力和适体-靶标复合物的结构表征的当前方法。关于产生适用于电化学传感的适体修饰电极的关键方面，如适当的生物受体固定策略和实验条件，以促进适体的方便锚定和稳定性，也讨论了。该综述还从最近的文献中总结了一些有效的小分子适应平台。
