Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications, 1650 Boulevard Lionel-Boulet, Varennes (Québec) J3X 1S2 Canada.
Environ Sci Technol. 2012 Oct 2;46(19):10697-703. doi: 10.1021/es301686k. Epub 2012 Sep 24.
The efficiency of current microcystin detection methods has been hampered by the low detection limits required in drinking water and that routine detection is restricted to a few of the congeners with high degree of undesired cross-reactivity. Here, we report the development of novel microcystin-targeting molecules and their application in microcystin detection. We have selected DNA aptamers from a diverse random library that exhibit high affinity and specificity to microcystin-LR, -YR, and -LA. We obtained aptamers that bind to all chosen congeners with high affinity with K(D) ranging from 28 to 60 nM. More importantly, we also obtained aptamers that are selective among the different congeners, with selectivity from 3-folds difference in binding affinity to total discrimination (K(D) of 50 nM versus nonspecific binding). Electrochemical aptasensors constructed with the selected aptamers were able to achieve sensitive and congener-specific microcystin detection with detection limit as low as 10 pM.
当前微囊藻毒素检测方法的效率受到饮用水中所需的低检测限的限制，并且常规检测仅限于具有高度非期望交叉反应性的几种同系物。在这里，我们报告了新型微囊藻毒素靶向分子的开发及其在微囊藻毒素检测中的应用。我们从多样化的随机文库中筛选出对微囊藻毒素-LR、-YR 和 -LA 具有高亲和力和特异性的 DNA 适体。我们获得了与所有所选同系物具有高亲和力的适体，其 KD 值范围为 28 至 60 nM。更重要的是，我们还获得了在不同同系物之间具有选择性的适体，其结合亲和力差异为 3 倍，完全区分（KD 为 50 nM 与非特异性结合）。使用所选适体构建的电化学适体传感器能够实现灵敏且同系物特异性的微囊藻毒素检测，检测限低至 10 pM。
