Ingenious Electrochemiluminescence Bioaptasensor Based on Synergistic Effects and Enzyme-Driven Programmable 3D DNA Nanoflowers for Ultrasensitive Detection of Aflatoxin B1

Abstract

Aflatoxin B1 (AFB1), one of the most toxic mycotoxins, has undergone a wide range of studies over the years. The development of rapid, simple, and sensitive analytical methods remains a major challenge for the accurate detection of AFB1 in foodstuffs. In this study, we designed an enhanced and stable ingenious electrochemiluminescence bioaptasensor (IEC-BA) for ultrasensitive detection of AFB1 based on the synergistic effects and enzyme-driven programmable assembled 3D DNA nanoflowers (EPDNs). This synergistic effect was comprised by the competitive impact on auxiliary probes (AP) and the cutting effect of the Hae III. Compared to the traditional aptamer directcompetition method, the synergistic effects ensured that the aptamer was more efficiently and adequately competed away by the target. Also, the redundant double-stranded probes were removed, which greatly facilitates simple, quick, and sensitive detection of AFB1. Besides, a large chunk of positively charged Ru(II) complexes (Ru(bpy) 3 2+ ) was accumulated by the utilization of EPDNs, which resulted in tremendous improvement of the sensitivity of the designed method. Thus, even in the presence of trace amounts of AFB1, a sharply visual electrochemiluminescent signal was generated. The proposed method can realize the quantification of AFB1 with a good linear range from 1 ppt (pg mL −1 ) to 5 ppb (ng mL −1 ) with a detection limit of 0.27 ppt. In addition, it can also be successfully applied for the analysis of AFB1 in a peanut and wheat, with total recoveries ranging from 93.7 to 106.6%. Furthermore, the IEC-BA also exhibited good selectivity, reproducibility, and stability, revealing prospective applications of food safety monitoring and environmental analysis.

An In Situ Generated Prussian Blue Nanoparticle-Mediated Multimode Nanozyme-Linked Immunosorbent Assay for the Detection of Aflatoxin B1

“…Aflatoxin B1 (AFB1) is one of the most toxic mycotoxins and is frequently detected in agricultural products. In early 2002, AFB1 has been classified as a group 1 carcinogen by the International Agency for Research on Cancer due to its mutagenicity, teratogenicity, and carcinogenicity. , The Food and Agriculture Organization (FAO) has set maximum allowable limits (1.0–20 ng/g) for AFB1 in foodstuffs . To meet the requirements of food safety and minimize manpower consumption in supervision and trade losses, researchers continuously pursue methods for the rapid, portable, and ultrasensitive quantification of AFB1 .…”

Nanomaterials-Based Electrochemiluminescence Biosensors for Food Analysis: Recent Developments and Future Directions

“…Under optimal conditions, the proposed immunosensor exhibited a good linear range from 0.01 to 100 ng/mL with a detection limit of 0.0039 ng/mL (S/N = 3). To improve the sensitivity of AFB1 assays, Yan et al designed an enhanced ECL aptasensor for AFB1 detection using enzyme-assisted 3D DNA nanoflowers for signal amplification [ 48 ], and this aptasensor can achieve the quantification of AFB1 with a good linear range from 1 pg/mL to 5 ng/mL with a detection limit of 0.27 pg/mL due to the synergistic effects between the competitive reaction and enzyme-assisted amplification strategy.…”

“… Analytes Sample Matrix Limit of Detection Linear Range Ref. Aflatoxin B1 peanut 0.17 ng/mL 3.13–125.00 ng/mL [ 46 ] Aflatoxin B1 milk 3.9 pg/mL 0.01–100 ng/mL [ 47 ] Aflatoxin B1 peanut, wheat 0.27 pg/mL 1 pg/mL–5 ng/mL [ 48 ] Ochratoxin A corn 0.17 pg/mL 0.0005–50 ng/mL [ 49 ] Ochratoxin A grain 3 pg/mL 0.01–500 ng/mL [ 50 ] Ochratoxin A wine, beer 0.012 nM 0.05 nM–5 nM [ 51 ] Zearalenone corn flour 1 fg/mL 10 fg/mL–10 ng/mL [ 54 ] …”

Mycotoxins Detection Based on Electrochemical Approaches

“…When OTA was added, walker hybridized with Cy5-labeled DNA autonomously, and released abundant Cy5-DNA with assistance of a cleavage endonucase, resulting in the recovery of ECL signal. An ingenious ECL bioaptasensor was constructed by enzyme-driven programmable assembled 3D DNA nano-flowers (EPDNs) [114]. In the sensing process, EPDNs/Ru(II) (Ru(bpy) 3…”