Wu Shijia, Duan Nuo, Zhang Weixiao, Zhao Sen, Wang Zhouping
State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi 214122, China.
State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi 214122, China.
Anal Biochem. 2016 Sep 1;508:58-64. doi: 10.1016/j.ab.2016.05.024. Epub 2016 Jun 16.
Patulin (PAT) is a kind of mycotoxin that has serious harmful impacts on both food quality and human health. A high-affinity ssDNA aptamer that specifically binds to patulin was generated using systemic evolution of ligands by exponential enrichment (SELEX) assisted by graphene oxide (GO). After 15 rounds of positive and negative selection, a highly enriched ssDNA pool was sequenced and the representative sequences were subjected to binding assays to evaluate their affinity and specificity. Of the eight aptamer candidates tested, the sequence PAT-11 bound to patulin with high affinity and excellent selectivity with a dissociation constant (Kd) of 21.83 ± 5.022 nM. The selected aptamer, PAT-11, was subsequently used as a recognition element to develop a detection method for patulin based on an enzyme-chromogenic substrate system. The colorimetric aptasensor exhibited a linear range from 50 to 2500 pg mL(-1), and the limit of detection was found to be 48 pg mL(-1). The results indicated that GO-SELEX technology was appropriate for the screening of aptamers against small-molecule toxins, offering a promising application for aptamer-based biosensors.
展青霉素（PAT）是一种对食品质量和人体健康都有严重危害的霉菌毒素。利用氧化石墨烯（GO）辅助的指数富集配体系统进化技术（SELEX），生成了一种能特异性结合展青霉素的高亲和力单链DNA适配体。经过15轮正负筛选后，对高度富集的单链DNA文库进行测序，并对代表性序列进行结合试验，以评估它们的亲和力和特异性。在所测试的8个适配体候选序列中，序列PAT-11与展青霉素具有高亲和力和优异的选择性，解离常数（Kd）为21.83±5.022 nM。随后，将筛选得到的适配体PAT-11用作识别元件，开发了一种基于酶显色底物系统的展青霉素检测方法。该比色适配体传感器的线性范围为50至2500 pg mL-1，检测限为48 pg mL-1。结果表明，GO-SELEX技术适用于筛选针对小分子毒素的适配体，为基于适配体的生物传感器提供了广阔的应用前景。
