Lateral flow immunoassay (LFIA) for the detection of lethal amatoxins from mushrooms

Authors: Bever, Candace; ADAMS, CATHARINE - University Of California; Hnasko, Robert; Cheng, Luisa; STANKER, LARRY - Former ARS Employee

Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/31/2020
Publication Date: 4/17/2020
Citation: Bever, C.R., Adams, C.A., Hnasko, R.M., Cheng, L.W., Stanker, L.H. 2020. Lateral flow immunoassay (LFIA) for the detection of lethal amatoxins from mushrooms. PLoS One. 15(4). https://doi.org/10.1371/journal.pone.0231781.
DOI: https://doi.org/10.1371/journal.pone.0231781

Interpretive Summary: One of the deadliest natural toxins is amatoxins and it is found in a small variety of mushrooms. Methods to detect amatoxins from mushrooms are labor-intensive and expensive. In this paper, we report a rapid and portable detection method for amatoxins. We generated an antibody-based test strip that takes ~10 mins for the visual determination of presence or absence of amatoxins in an extracted mushroom sample. We tested over 100 wild mushrooms and accurately identified 6 species that were known to contain amatoxins. The speed of analysis and lack of requirement for trained personnel and expensive instrumentation, means that this test strip method would be a great improvement over the current gold standard detection methods. This simple test can aid in mushroom identification and with amatoxin poisoning cases.

Technical Abstract: The mushroom poison that causes the most deaths is the class of toxins known as amatoxins. Current methods to sensitively and selectively detect these toxins are limited by the need for expensive equipment, or they lack accuracy due to cross-reactivity with other chemicals found in mushrooms. In this work, we report the development of a competition-based lateral flow immunoassay (LFIA) for the rapid, portable, selective, and sensitive detection of amatoxins. Our assay clearly indicates the presence of 10 ng/mL of a-AMA or '-AMA and the method including extraction and detection can be completed in approximately 10 minutes. The test can be easily read by eye and has a presumed shelf-life of at least 1 year. From testing 110 wild mushrooms, the LFIA identified 6 out of 6 species that were known to contain amatoxins. Other poisonous mushrooms known not to contain amatoxins tested negative by LFIA. This LFIA can be used to quickly identify amatoxin-containing mushrooms.