Zhou Wenhu, Huang Po-Jung Jimmy, Ding Jinsong, Liu Juewen
Department of Pharmaceutics, School of Pharmaceutical Sciences, Central South University, Tongzipo Road #172, Changsha 410013, Hunan, PR China.
Analyst. 2014 Jun 7;139(11):2627-40. doi: 10.1039/c4an00132j.
Aptamers are single-stranded nucleic acids that selectively bind to target molecules. Most aptamers are obtained through a combinatorial biology technique called SELEX. Since aptamers can be isolated to bind to almost any molecule of choice, can be readily modified at arbitrary positions and they possess predictable secondary structures, this platform technology shows great promise in biosensor development. Over the past two decades, more than one thousand papers have been published on aptamer-based biosensors. Given this progress, the application of aptamer technology in biomedical diagnosis is still in a quite preliminary stage. Most previous work involves only a few model aptamers to demonstrate the sensing concept with limited biomedical impact. This Critical Review aims to summarize progress that might enable practical applications of aptamers for biological samples. First, general sensing strategies based on the unique properties of aptamers are summarized. Each strategy can be coupled to various signaling methods. Among these, a few detection methods including fluorescence lifetime, flow cytometry, upconverting nanoparticles, nanoflare technology, magnetic resonance imaging, electronic aptamer-based sensors, and lateral flow devices have been discussed in more detail since they are more likely to work in a complex sample matrix. The current limitations of this field include the lack of high quality aptamers for clinically important targets. In addition, the aptamer technology has to be extensively tested in a clinical sample matrix to establish reliability and accuracy. Future directions are also speculated to overcome these challenges.
适体是能选择性结合靶分子的单链核酸。大多数适体是通过一种称为指数富集的配体系统进化技术（SELEX）的组合生物学技术获得的。由于适体可以被分离出来以结合几乎任何选定的分子，能在任意位置进行轻松修饰，并且具有可预测的二级结构，这种平台技术在生物传感器开发中显示出巨大的前景。在过去二十年中，已经发表了一千多篇关于基于适体的生物传感器的论文。尽管取得了这样的进展，但适体技术在生物医学诊断中的应用仍处于相当初步的阶段。以前的大多数工作仅涉及少数模型适体，以展示传感概念，对生物医学的影响有限。这篇综述旨在总结可能使适体在生物样本中得到实际应用的进展。首先，总结了基于适体独特性质的一般传感策略。每种策略都可以与各种信号方法相结合。其中，由于荧光寿命、流式细胞术、上转换纳米颗粒、纳米耀斑技术、磁共振成像、基于电子适体的传感器和侧向流动装置等几种检测方法更有可能在复杂的样本基质中发挥作用，因此对它们进行了更详细的讨论。该领域目前的局限性包括缺乏针对临床重要靶点的高质量适体。此外，适体技术必须在临床样本基质中进行广泛测试，以确定其可靠性和准确性。还推测了克服这些挑战的未来方向。
