Laboratory for Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium.
Anal Chem. 2012 Feb 7;84(3):1669-76. doi: 10.1021/ac202960b. Epub 2012 Jan 19.
Polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) that resist natural degradation and bioaccumulate in nature. Combined with their toxicity, this leads them to cause cancer and other health hazards. Thus, there is a vital need for rapid and sensitive methods to detect PCB residues in food and in the environment. In this study, PCB-binding DNA aptamers were developed using PCB72 and PCB106 as targets for aptamer selection. Aptamers are synthetic DNA recognition elements which form unique conformations that enable them to bind specifically to their targets. Using in vitro selection techniques and fluorometry, an aptamer that binds with nanomolar affinity to both the PCBs has been developed. It displayed high selectivity to the original target congeners and limited affinity toward other PCB congeners (105, 118, 153, and 169), suggesting general specificity for the basic PCB skeleton with varying affinities for different congeners. This aptamer provides a basis for constructing an affordable, sensitive, and high-throughput assay for the detection of PCBs in food and environmental samples and offers a promising alternative to existing methods of PCB quantitation. This study therefore advances aptamer technology by targeting one of the highly sought-after POPs, for the first time ever recorded.
多氯联苯（PCBs）是持久性有机污染物（POPs），它们难以自然降解，并在自然界中生物累积。再加上它们的毒性，这导致它们会引发癌症和其他健康危害。因此，迫切需要快速和敏感的方法来检测食品和环境中的 PCB 残留。在这项研究中，使用 PCB72 和 PCB106 作为适体选择的靶标，开发了与 PCB 结合的 DNA 适体。适体是一种合成的 DNA 识别元件，它形成独特的构象，使它们能够特异性地结合其靶标。通过体外选择技术和荧光法，开发出了一种对两种 PCB 都具有纳摩尔亲和力的适体。它对原始目标同系物表现出高选择性，对其他 PCB 同系物（105、118、153 和 169）的亲和力有限，这表明它对基本的 PCB 骨架具有一般特异性，对不同的同系物具有不同的亲和力。该适体为构建用于检测食品和环境样品中 PCB 的经济实惠、敏感且高通量的检测方法提供了基础，并为现有的 PCB 定量方法提供了有前景的替代方法。因此，这项研究通过靶向一种高需求的 POP，首次推进了适体技术。
