Development and Characterization of a Piezoelectric Immunosensor for Determination of Domoic Acid in Food Samples

In the present study a label-free piezoelectric crystal immunosensor, based on an indirect competitive assay format, for the detection of domoic acid (DA) in shellfish is described. After physical absorption of the conjugate on the gold surface of the quartz crystals a competition step was performed by putting in contact with the crystal a solution containing the specific polyclonal antibody against domoic acid and the DA as free toxin. The build up of mass on the crystal surface, registered as a frequency decrease by the quartz crystal microbalance, can be related to the amount of free toxin in the solution in the 0-10 µg/g range. The sensor is capable to measure domoic acid at the established regulatory level (20 µg/g) after a 1:4 (v/v) dilution of the sample extract. The repeatability obtained by using three different crystals was lower than 7%. Regeneration assays have shown the possibility to reuse the modified surface by using 0.1 M NaOH as dissociation agent. The sensor could have application as screening method for compliance with European food legislation.

RODRIGUEZ Ana;  BARRERO Josefa;  PAPADOPOULOU Andri;  ROSSI Francois; 

2009-06-05

WISSENSCHAFTLICHE VERLAG MBH

JRC49928

0012-0413,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC49928,