Development of a graphene oxide nanosheet and double-stranded DNA structure based fluorescent “signal off” aptasensor for ochratoxin A detection in malt

Food Chemistry: X

Linzhi Kang¹  Lidong Zhou²  Meng Wang³  Haiping Zhao³  Qing Zhang⁴  Linchun Shi⁴  Pengfei Yue⁵  Weijun Kong⁶ 

[1] Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100193, China;Beijing Research Center for Agricultural Standards and Testing, Beijing 100097, China;Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100193, China;Key Laboratory of Modern Preparation of TCM, Ministry of Education, Pharmacy College, Jiangxi University of Traditional Chinese Medicine, Nanchang 330004, China;School of Nursing, Jiangxi University of Traditional Chinese Medicine, Nanchang 330004, China;School of Traditional Chinese Medicine, Jiangxi University of Traditional Chinese Medicine, Nanchang 330004, China;

关键词: Ochratoxin A;    Malt;    Fluorescent aptasensor;    Graphene oxide nanosheet;    Double-stranded DNA;   

DOI  :  

来源: DOAJ

【 摘 要 】

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.

【 授权许可】

Unknown