Luminescence method for detection of aflatoxin B1 using ATP-releasing nucleotides

Aflatoxin Contamination: An Overview on Health Issues, Detection and Management Strategies

Aflatoxins (AFs) represent one of the main mycotoxins produced by Aspergillus flavus and Aspergillus parasiticus, with the most prevalent and lethal subtypes being AFB1, AFB2, AFG1, and AFG2. AFs are responsible for causing significant public health issues and economic concerns that affect consumers and farmers globally. Chronic exposure to AFs has been linked to liver cancer, oxidative stress, and fetal growth abnormalities among other health-related risks. Although there are various technologies, such as physical, chemical, and biological controls that have been employed to alleviate the toxic effects of AF, there is still no clearly elucidated universal method available to reduce AF levels in food and feed; the only mitigation is early detection of the toxin in the management of AF contamination. Numerous detection methods, including cultures, molecular techniques, immunochemical, electrochemical immunosensor, chromatographic, and spectroscopic means, are used to determine AF contamination in agricultural products. Recent research has shown that incorporating crops with higher resistance, such as sorghum, into animal feed can reduce the risk of AF contamination in milk and cheese. This review provides a current overview of the health-related risks of chronic dietary AF exposure, recent detection techniques, and management strategies to guide future researchers in developing better detection and management strategies for this toxin.

An efficient aggregation-induced electrochemiluminescent immunosensor by using TiO2 nanoparticles as coreaction accelerator and energy donor for aflatoxin B1 detection

Herein, we fabricated a label-free ECL immunosensor for aflatoxin B₁ (AFB₁) detection. In this system, a small organic aggregation-induced electrochemiluminescence luminophore, 2,5-di-tetraphenylethylene-ylthiazolo [5,4-d] thiazole, was designed, named TPETTZ. Polyaniline-wrapped TiO₂ nanoparticles (PANI/TiO₂ NPs) complex was synthesized through one-step in situ oxidation polymerization of aniline, and performed excellent electrical conductivity and abundant amino groups. As an ECL accelerator, TiO₂ nanoparticles (TiO₂ NPs) promoted the oxidation of tri-n-propylamine (TPA) to generate more TPA^•; in addition, it also acted as a donor to improve the ECL intensity of TPETTZ (acceptor) through electrochemiluminescence resonance energy transfer (ECL-RET). Encouraged by the above, under the existence of TPA, TPETTZ displayed a strong and continuously stable ECL_anode signal due to the introduction of PANI/TiO₂ NPs. Therefore, the immunosensor was constructed for AFB₁ detection based on the quenching effect of target on the ECL signal, and a linearly decreasing ECL signal was obtained as the increasement of AFB₁ in the range of 75 fg/mL to 100 ng/mL, with a lower detection limit of 27.5 fg/mL. Moreover, the as-prepared sensing platform performed a satisfactory anti-interference, stability, and reproducibility, and appeared a good accuracy in walnut sample analysis, presenting a promising application in the future.