Aggregation-Induced Enhancement Electrochemiluminescence of Ag Nanoribbons as a Signal Probe for Ultrasensitive Detection of the Halogenase Gene Segment from Aspergillus Ochratoxin.

Abstract

Here, an electrochemiluminescence (ECL) biosensor was developed based on aggregation-induced enhancement ECL of Ag nanoribbons (Ag NRs) as a signal probe and the mismatched bases-fueled DNA walker as the amplification strategy for ultrasensitive detection of the halogenase gene segment (target) from aspergillus ochratoxin to evaluate fungi capable of producing ochratoxin in dairy products. Compared with the existing agminated NCs, the Ag NRs displayed dramatically enhanced ECL emission due to effective electron transfer and less energy dissipation of excited-state Ag NRs based on the metallophilic interaction of Ag(I)-Ag(I). Impressively, the target was conversed mismatched bases-DNA walker to trigger a significant ECL response through toehold-mediated strand displacement amplification. Thus, the strategy realized trace analysis of the halogenase gene segment with a detection limit of 45 aM, which ushered a new detection method for toxin determination in the previous stage of toxin biosynthesis to protect people from toxic damage.