Hierarchically porous Zr-MOFs labelled methylene blue as signal tags for electrochemical patulin aptasensor based on ZnO nano flower

SENSORS AND ACTUATORS B-CHEMICAL

卷:294

Article

He, Baoshan¹  Dong, Xiaoze¹ 

[1] Henan Univ Technol, Henan Key Lab Cereal & Oil Food Safety Inspect &, Sch Food Sci & Technol, Lianhua Rd 100, Zhengzhou 450001, Henan, Peoples R China

关键词: Electrochemistry;    Zr-MOF;    PAT;    Rapid detection;    Aptamer;   

DOI  :  10.1016/j.snb.2019.05.045

来源: Elsevier

【 摘 要 】

In this work, the feasibility of a novel sensitive electrochemistry aptasensor for the detection of patulin (PAT) using hierarchically porous metal organic framework@methylene blue connection aptamer as signal tags was demonstrated. The substrate electrode of the aptasensor was prepared by electrodeposited gold nanoparticles (AuNPs) on chitosan-zinc oxide nano flower-modified electrode. Subsequently, the complementary single-stranded DNA was attached to the surface of the modified electrode by Au-S bond. Signal tags self-assemble on the surface of modified electrodes by aptamer-cDNA binding, while methylene blue as mediator for electrochemical detection. Thanks to the large specific surface area provided by zinc oxide nano flower, the electrode can load more signal tags and AuNPs to achieve signal amplification. In presence of PAT, Apt preferentially binds to PAT, causing dissociation of some Apt-cDNA and releasing some signal tags leading, resulting in decreased electrical signals. Under optimal conditions, the change in electrochemical signal was proportional to the logarithm of PAT concentration, from 5 x 10(-8)-5 x 10(-1) mu g mL(-1), and the detection limit was estimated to be 1.46 x 10(-8) mu g mL(-1). The aptasensor exhibited aceptable reproducibility, renewability, long-term stability and specificity. Moreover, aptasensor was reliable in determination of PAT in spiked apple juice samples.

【 授权许可】

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