Generation of a panel of high affinity antibodies and development of a biosensor-based immunoassay for the detection of okadaic acid in shellfish

Abstract

Okadaic acid (OA) and its derivatives, DTX-1 and DTX-2, are marine biotoxins associated with diarrhetic shellfish poisoning. Routine monitoring of these toxins relies on the mouse bioassay. However, due to the technical unreliability and animal usage of this bioassay, there is always a need for convenient and reliable alternative assay methods. A panel of monoclonal antibodies against OA was generated and the most suitable was selected for biosensor-based assay development using surface plasmon resonance. The cross reactivity of the selected antibody with DTX-1 was found to be 73%, confirming the antibody suitability for both OA and DTX detection. The OA and derivative assay was designed as an inhibition assay covering the concentrations 1-75 ng/ml, with a sensitivity of 22.4 ng/ml. The assay was highly reproducible and preliminary validation showed no matrix interference from mussel extracts and good recovery of added standard in mussel extracts, with %CV of <9.3%. This assay could provide a useful and convenient screening tool for OA and its derivatives with a comprehensive extraction protocol for shellfish monitoring programmes.

Selective enrichment and quantification of okadaic acid in shellfish using an immunomagnetic‐bead‐based liquid chromatography with tandem mass spectrometry assay

“…One CRM‐DSP‐Mus‐c sample that contained OA, DTX‐1, and DTX‐2 was also used in the specificity experiment. In one study , the cross‐reactivity of the monoclonal antibody against OA was found to be 73% with DTX‐1, which confirmed its suitability for both OA and DTX‐1 detection. In our study, nonspecific binding with YTX, PTX‐2, and DTX‐1 was not detected.…”

Sensitive detection of the okadaic acid marine toxin in shellfish by Au@Pt NPs/horseradish peroxidase dual catalysis immunoassay

“…It was rather sensitive and might be better than the sensitivity (IC 10 ) of most ic-ELISA methods (0.06–7.4 ng mL −1 in buffer, shown in Table S3†) reported previously. 8,9,40,41…”

Selection and application of aptamers with high-affinity and high-specificity against dinophysistoxin-1

“…56 It can monitor the surface property of the sensor, when the immobilized ligand is combined with the target molecule by biolayer interferometry technology in real time. 57 At this stage, there have been reports of the BLI sensors used on small molecule detection. 38,50 We performed a series of measurements on the newly developed BLI sensor in the concentration range of 40-600 nM to evaluate the feasibility and stability of the sensor (Fig.…”

“…Reports on the OA aptasensor at this stage indicated that it had high specicity for OA, while it is unable to detect DTX-1. 57 Repeatability and specicity are essential for the aptasensor. In order to test the repeatability of the aptasensor, we executed repeated measurements on the 100 nM DTX-1 solution and collected the response.…”