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Updated: Jul 13, 2025
Development of an Electrochemical DNA Biosensor to Detect a Foodborne Pathogen
Published on: June 3, 2018
A novel ternary Y-DNA walker amplification strategy designed fluorescence aptasensor based on Au@SiO2@Fe3O4
Xiaoze Dong1, Shuo Qi1, Mingwei Qin1
1State Key Laboratory of Food Science and Technology, International Joint Laboratory On Food Safety, Jiangnan University, Wuxi, 214122, China.
Abstract:
A novel ternary Y-DNA walker amplification strategy designed fluorescence aptasensor based on Au@SiO2@Fe3O4 nanomaterials for ultrasensitive and specific ochratoxin A detection in food samples is presented. Au@SiO2@Fe3O4 nanomaterials provide the loading platform as well as separation and recovery properties for the ternary Y-DNA walker. The ternary Y-DNA walker is designed to be driven by Nb.BbvCI cleaving a large number of FAM probes to achieve signal amplification. Since Ochratoxin A (OTA) can bind to the constituent aptamer in the ternary Y-DNA walker, adding OTA will destroy the structure of the ternary Y-DNA walker, thereby inhibiting the driving process of the walker. After optimization of various parameters, a standard curve was obtained from 100 to 0.05 ng·mL-1 of OTA with the limit of determination of 0.027 ng·mL-1. The spiked recovery of peanut samples by this method was 82.00-93.30%, and the aptasensor showed excellent specificity and long-term stability. This simple, robust, and scalable oligonucleotide chain-based ternary Y-DNA walker can provide a general signal amplification strategy for trace analysis.
