Multiplex Lateral Flow Assay and the Sample Preparation Method for the Simultaneous Detection of Three Marine Toxins

A multiplex lateral flow immunoassay (LFA) has been developed to detect the primary marine biotoxin groups: amnesic shellfish poisoning toxins, paralytic shellfish poisoning toxins, and diarrhetic shellfish poisoning toxins. The performance characteristics of the multiplex LFA were evaluated for its suitability as a screening method for the detection of toxins in shellfish. The marine toxin-specific antibodies were class-specific, and there was no cross-reactivity between the three toxin groups. The test is capable of detecting all three marine toxin groups, with working ranges of 0.2-1.5, 2.5-65.0, and 8.2-140.3 ng/mL for okadaic acid, saxitoxin, and domoic acid, respectively. This allows the multiplex LFA to detect all three toxin groups at the EU regulatory limits, with a single sample extraction method and dilution volume. No matrix effects were observed on the performance of the LFA with mussel samples spiked with toxins. The developed LFA uses a simple and pocket-sized, portable Cube Reader to provide an accurate result. We also evaluated the use of this Cube Reader with commercially available monoplex lateral flow assays for marine toxins.

Automated summary

A multiplex lateral flow immunoassay has been developed to detect marine biotoxins, with specific antibodies for each toxin group. The assay is capable of accurately detecting okadaic acid, saxitoxin, and domoic acid within EU regulatory limits. It offers a simple and portable solution for toxin screening in shellfish.