10.1021/acs.jafc.8b05652.s001 Ingunn A. Samdal Ingunn A. Samdal Kjersti E. Løvberg Kjersti E. Løvberg Anja B. Kristoffersen Anja B. Kristoffersen Lyn R. Briggs Lyn R. Briggs Jane Kilcoyne Jane Kilcoyne Craig J. Forsyth Craig J. Forsyth Christopher O. Miles Christopher O. Miles A Practical ELISA for Azaspiracids in Shellfish via Development of a New Plate-Coating Antigen American Chemical Society 2019 Current methods novel AZAs AZA reference materials LC-MS food poisoning New Plate-Coating Antigen Azaspiracids Practical ELISA AZA -3 Puget Sound AZA -1-containing plate-coating conjugate R 2 OVA screening samples ELISA method 2019-02-14 21:05:23 Journal contribution https://acs.figshare.com/articles/journal_contribution/A_Practical_ELISA_for_Azaspiracids_in_Shellfish_via_Development_of_a_New_Plate-Coating_Antigen/7722149 Azaspiracids (AZAs) are a group of biotoxins that appear periodically in shellfish and can cause food poisoning in humans. Current methods for quantifying the regulated AZAs are restricted to LC-MS but are not well suited to detecting novel and unregulated AZAs. An ELISA method for total AZAs in shellfish was reported recently, but unfortunately, it used relatively large amounts of the AZA-1-containing plate-coating conjugate, consuming significant amounts of pure AZA-1 per assay. Therefore, a new plate-coater, OVA–cdiAZA1 was produced, resulting in an ELISA with a working range of 0.30–4.1 ng/mL and a limit of quantification of 37 μg/kg for AZA-1 in shellfish. This ELISA was nearly twice as sensitive as the previous ELISA while using 5-fold less plate-coater. The new ELISA displayed broad cross-reactivity toward AZAs, detecting all available quantitative AZA reference materials as well as the precursors to AZA-3 and AZA-6, and results from shellfish analyzed with the new ELISA showed excellent correlation (<i>R</i><sup>2</sup> = 0.99) with total AZA-1–10 by LC-MS. The results suggest that the new ELISA is suitable for screening samples for total AZAs, even in cases where novel AZAs are present and regulated AZAs are absent, such as was reported recently from Puget Sound and the Bay of Naples.