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Updated: Sep 25, 2025
Development of an Electrochemical DNA Biosensor to Detect a Foodborne Pathogen
Published on: June 3, 2018
Development of a graphene oxide nanosheet and double-stranded DNA structure based fluorescent "signal off" aptasensor
Qing Zhang1,2, Linzhi Kang3, Pengfei Yue1
1Key Laboratory of Modern Preparation of TCM, Ministry of Education, Pharmacy College, Jiangxi University of Traditional Chinese Medicine, Nanchang 330004, China.
Abstract:
A "signal off" fluorescent aptasensor based on graphene oxide (GO) nanosheet and double-stranded DNA structure was fabricated for OTA detection. In the absence of OTA, the aptamer and its complementary DNA (cDNA) formed double-stranded conjugates that could coexist with GO, presenting fluorescence responses. Then, the presented OTA was captured by the aptamers, causing the release of cDNA-FAM probes. The free probes were adsorbed by GO, leading to an OTA concentration-dependent fluorescence quenching through fluorescence resonance energy transfer. Under optimum conditions, the fluorescent aptasensor exhibited outstanding sensitivity with a LOD of 11 pg/mL and a wide dynamic range of 0.04-30 ng/mL. The selectivity of the aptasensor was confirmed against other four mycotoxins, and the feasibility and reliability were verified by determining OTA in the spiked malt samples with satisfactory recovery of 95.50%-112.05%. This aptasensing platform could be adapted to measure other mycotoxins by replacing the aptamer sequences for food safety.
