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We report the development of a competitive ELISA-based origami microfluidic paper-based analytical device (μPAD) for the detection of mycotoxins in animal feed material. The μPAD was patterned using the wax printing technique with the design of a testing pad in the middle and two absorption pads at the side. Anti-mycotoxin antibodies were effectively immobilized on chitosan-glutaraldehyde-modified sample reservoirs in the μPAD. The determination of zearalenone, deoxynivalenol, and T-2 toxin in corn flour was successfully achieved by performing competitive ELISA on the μPAD in 20 min. Colorimetric results were easily distinguished by the naked eye with a detection limit of 1 µg/mL for all three mycotoxins. The μPAD integrated with competitive ELISA holds potential for practical applications in the livestock industry for rapid, sensitive, and cost-effective detection of different mycotoxins in animal feed materials., (© 2023. Springer-Verlag GmbH Germany, part of Springer Nature.)

Mycotoxins produced by different species of fungi may coexist in cereals and feedstuffs, and could be highly toxic for humans and animals. For quantification of multiple mycotoxins in cereals, we developed a paper-based mycotoxin immune-affinity array. First, paper-based microzone arrays were fabricated by photolithography. Then, monoclonal mycotoxin antibodies were added in a copolymerization reaction with a cross-linker to form an immune-affinity monolith on the paper-based microzone array. With use of a competitive immune-response format, paper-based mycotoxin immune-affinity arrays were successfully applied to detect mycotoxins in samples. The detection limits for deoxynivalenol, zearalenone, T-2 toxin, and HT-2 toxin were 62.7, 10.8, 0.36, and 0.23 μg·kg -1 , respectively, which meet relevant requirements for these compounds in food. The recovery rates were 81-86% for deoxynivalenol, 89-117% for zearalenone, 79-86% for T-2 toxin, and 78-83% for HT-2 toxin, and showed the paper-based immune-affinity arrays had good reproducibility. In summary, the paper-based mycotoxin immune-affinity array provides a sensitive, rapid, accurate, stable, and convenient platform for detection of multiple mycotoxins in agro-foods. Graphical abstract Paper-based immune-affinity monolithic array. DON deoxynivalenol, HT-2 HT-2 toxin, T-2 T-2 toxin, PEGDA polyethylene glycol diacrylate, ZEN zearalenone.

In this study, aflatoxin B 1 (AFB 1 ) toxicity toward the earthworm Eisenia fetida (Savigny 1826) was evaluated in contact paper test systems containing distilled water and ethanol or 20 to 400 μg/ml of AFB 1 over 72 h of exposure. The results indicated that AFB 1 could induce significant damage to earthworms (coiling, curling, excessive mucus secretion, clitellum swelling) at greater than 75 μg/ml. Moreover, AFB 1 had harmful effects on E. fetida (degenerative changes such as bulging of the clitella regions) at levels higher than 150 μg/ml. The calculated LD 50 was 168.5 μg/ml. These findings confirm that E. fetida and standardized methods based on this organism (OECD 207 1984) are applicable and useful in mycotoxin related toxicity studies.

A semi-quantitative and quantitative multi-immunochromatographic (ICA) strip detection assay was developed for the simultaneous detection of twenty types of mycotoxins from five classes, including zearalenones (ZEAs), deoxynivalenols (DONs), T-2 toxins (T-2s), aflatoxins (AFs), and fumonisins (FBs), in cereal food samples. Sensitive and specific monoclonal antibodies were selected for this assay. The semi-quantitative results were obtained within 20 min by the naked eye, with visual limits of detection for ZEAs, DONs, T-2s, AFs and FBs of 0.1-0.5, 2.5-250, 0.5-1, 0.25-1 and 2.5-10 μg kg(-1), and cut-off values of 0.25-1, 5-500, 1-10, 0.5-2.5 and 5-25 μg kg(-1), respectively. The quantitative results were obtained using a hand-held strip scan reader, with the calculated limits of detection for ZEAs, DONs, T-2s, AFs and FBs of 0.04-0.17, 0.06-49, 0.15-0.22, 0.056-0.49 and 0.53-1.05 μg kg(-1), respectively. The analytical results of spiked samples were in accordance with the accurate content in the simultaneous detection analysis. This newly developed ICA strip assay is suitable for the on-site detection and rapid initial screening of mycotoxins in cereal samples, facilitating both semi-quantitative and quantitative determination.

Mold deterioration of historical documents in archives and libraries is a frequent and complex phenomenon that may have important economic and cultural consequences. In addition, exposure to toxic fungal metabolites might produce health problems. In this work, samples of broths of fungal species isolated from the documentary material and from indoor environmental samples of the Archive of Bogotá have been analyzed to investigate the presence of mycotoxins. High resolution mass spectrometry made possible to search for a large number of mycotoxins, even without reference standards available at the laboratory. For this purpose, a screening strategy based on ultra-high pressure liquid chromatography coupled to quadrupole-time of flight mass spectrometry (UHPLC-QTOF MS) under MS(E) mode was applied. A customized home-made database containing elemental composition for around 600 mycotoxins was compiled. The presence of the (de)protonated molecule measured at its accurate mass was evaluated in the samples. When a peak was detected, collision induced dissociation fragments and characteristic isotopic ions were also evaluated and used for tentative identification, based on structure compatibility and comparison with literature data (if existing). Up to 44 mycotoxins were tentatively identified by UHPLC-QTOF MS. 34 of these tentative compounds were confirmed by subsequent analysis using a targeted LC-MS/MS method, supporting the strong potential of QTOF MS for identification/elucidation purposes. The presence of mycotoxins in these samples might help to reinforce safety measures for researchers and staff who work on reception, restoration and conservation of archival material, not only at the Archive of Bogotá but worldwide., (Copyright © 2015 Elsevier Inc. All rights reserved.)

A strategy for aptamer-based biosensing termed linkage inversion assembled nano-aptasensors (LIANAs) is shown to be a generally applicable approach to the sensitive and specific detection of a target molecule in turn-on fluorescence solution-based and paper-based tests.

This study examined the efficacy of the following treatments to reduce selected fungal spore and mycotoxin levels on materials commonly found in home contents: (1) gamma irradiation at a 10-13 kiloGray exposure, (2) a detergent/bleach wash, and (3) a steam cleaning technique. A minimum of six replicates were performed per treatment. Paper, cloth, wood, and carpet were inoculated with either fungal spores (Stachybotrys chartarum, Aspergillus niger, Penicillium chrysogenum, or Chaetomium globosum) at 240,000 spores/2.54 cm2 of material or with the mycotoxins roridin A, T-2, and verrucarin A at 10 microg per 2.54 cm2 of material. Treatments were evaluated with an agar plating technique for fungal spores and a yeast toxicity culture assay for mycotoxins. Results showed that gamma irradiation inactivated fungal spores, but the treatment was not successful in inactivating mycotoxins. The washing technique completely inactivated or removed spores on all materials except for C. globosum, which was reduced on all items except paper (p < 0.05). Washing inactivated all mycotoxins on paper and cloth but not on carpet or untreated wood (p < 0.001). The steam cleaning treatment did not completely eliminate any fungal spores; however, it reduced P. chrysogenum numbers on all materials, C. globosum was reduced on wood and carpet, and S. chartarum was reduced on wood (p < 0.05). Steam cleaning was unsuccessful in inactivating any of the tested mycotoxins. These results show that the bleach/detergent washing technique was more effective overall in reducing spore and mycotoxin levels than gamma irradiation or steam cleaning. However, the other examined techniques were successful in varying degrees., (Copyright 2004 JOEH, LLC)