Chem. J. Chinese Universities ›› 2021, Vol. 42 ›› Issue (12): 3615.doi: 10.7503/cjcu20210409

• Analytical Chemistry • Previous Articles     Next Articles

Construction of a Label-free Electrochemical Ochratoxin Aptasensor Based on Pt Nanoparticles@ metal-organic Framework Nanomimetic Enzyme

LI Mei, XIA Xiaojuan, CHEN Zhixiong, YANG Meng, LI Ziying, YANG Tong, MENG Shuang, YANG Yunhui(), HU Rong()   

  1. Faculty of Chemistry and Chemical Engineering,Yunnan Normal University,Kunming 650500,China
  • Received:2021-06-16 Online:2021-12-10 Published:2021-08-11
  • Contact: YANG Yunhui,HU Rong E-mail:yyhui2002@aliyun.com;hudierong_168@163.com
  • Supported by:
    the National Natural Science Foundation of China(21765026)

Abstract:

Pt NPs@Mn-MOF nanocomposite material with peroxidase-like properties was used as electrode substrate, and a label-free electrochemical aptasensor was constructed by screen printing electrode for the detection of ochratoxin(OTA). Utilizing the nanomimetic enzyme characteristics of Pt NPs@Mn-MOF, Pt NPs@Mn-MOF was used as an electrode substrate to capture OTA aptamer chain and catalyze the reduction of H2O2 to generate current response signal. The introduction of OTA can obdurate the catalytic active sites of the nanomimetic enzyme, which leads to the decrease of current signal. In the range of 0.01—300 ng/mL, the current response value decreases gradually with the increase of OTA concentration. The current response signal was detected by the chronoamperometry, so the quantitative detection of OTA was realized indirectly. In addition, the aptasensor can be detected through a small U-disk type electrochemical workstation, which can be connected to a computer or a mobile phone for real-time detection. It has high detection sensitivity and good reproducibility, and the detection limit is as low as 3.33 pg/mL(S/N=3). The constructed aptasensor can be used for OTA detection in real corn samples, and shows potential application in mycotoxin detection.

Key words: Pt nanoparticle, Metal-organic framework, Nanomimetic enzyme, Aptasensor, Ochratoxin

CLC Number: 

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