A novel electrochemical aptasensor was developed for multiple signal amplification based on Au@Pt/MIL-101(Cr) as mimetic enzyme and RecJ_f Exo-assisted target recycling. For the detection of ochratoxin A (OTA), the catalytic ability of Au@Pt/MIL-101(Cr) was better than that of Au@Pt toward hydroquinone oxidation in the presence of H₂O₂, and the peak current increased by 48.3 %. The peak current obtained with RecJ_f Exo incubation increased by 140 % than that without RecJ_f Exo incubation. These results demonstrated that the synergistic effect of Au@Pt/MIL-101(Cr) and RecJ_f Exo realized the signal amplification and enhanced the sensitivity. The prepared aptasensor exhibited a wider linear range of OTA concentration from 0.001 ng/mL to 5 ng/mL with a lower LOD of 0.17 pg/mL. The aptasensor also showed good specificity, reproductibility, and repeatability toward OTA detection. For the application in the spiked white spirit, the obtained recovery was from 97 % to 106 %, indicating that the proposed aptasensor can be applied for OTA analysis in real samples.

基于Au @ Pt / MIL-101（Cr）作为模拟酶和RecJ _f Exo辅助靶循环，开发了一种用于多信号放大的新型电化学适体传感器。检测曲霉毒素A（OTA）时，在H ₂ O ₂存在下，Au @ Pt / MIL-101（Cr）的催化性能优于Au @ Pt对氢醌氧化的催化能力，峰值电流增加48.3％。RecJ _f Exo孵育的峰值电流比没有RecJ _f Exo孵育的峰值电流增加了140％。这些结果表明Au @ Pt / MIL-101（Cr）和RecJ _f的协同作用。Exo实现了信号放大并提高了灵敏度。制备的适体传感器显示的OTA浓度线性范围更广，从0.001 ng / mL到5 ng / mL，LOD较低，为0.17 pg / mL。适体传感器对OTA检测也显示出良好的特异性，可重复性和可重复性。对于加标白油中的应用，所获得的回收率为97％至106％，表明所提出的适体传感器可用于实际样品中的OTA分析。