Department of Bioengineering, Stanford University, 443 Via Ortega, MC 4245, Stanford, CA 94305, USA.
Chemistry Department, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada.
Toxins (Basel). 2014 Aug 15;6(8):2435-52. doi: 10.3390/toxins6082435.
Nucleic acid aptamers are emerging as useful molecular recognition tools for food safety monitoring. However, practical and technical challenges limit the number and diversity of available aptamer probes that can be incorporated into novel sensing schemes. This work describes the selection of novel DNA aptamers that bind to the important food contaminant ochratoxin A (OTA). Following 15 rounds of in vitro selection, sequences were analyzed for OTA binding. Two of the isolated aptamers demonstrated high affinity binding and selectivity to this mycotoxin compared to similar food adulterants. These sequences, as well as a truncated aptamer (minimal sequence required for binding), were incorporated into a SYBR® Green I fluorescence-based OTA biosensing scheme. This label-free detection platform is capable of rapid, selective, and sensitive OTA quantification with a limit of detection of 9 nM and linear quantification up to 100 nM.
核酸适体作为食品安全监测的有用分子识别工具正在兴起。然而，实际和技术挑战限制了可纳入新型传感方案的可用适体探针的数量和多样性。本工作描述了对重要食品污染物赭曲霉毒素 A（OTA）具有结合能力的新型 DNA 适体的选择。经过 15 轮体外选择，对 OTA 结合的序列进行了分析。两种分离的适体与这种真菌毒素相比，对这种真菌毒素表现出高亲和力结合和选择性。这些序列以及一个截断的适体（结合所需的最小序列）被纳入 SYBR® Green I 荧光 OTA 生物传感方案中。这种无标记检测平台能够快速、选择性和灵敏地定量 OTA，检测限为 9 nM，线性定量可达 100 nM。
