Modified paramagnetic beads in a microfluidic system for the determination of Zearalenone in feedstuffs Samples

NANCY V. PANINI; ELOY SALINAS; GERMÁN A. MESSINA; JULIO RABA

FOOD CHEMISTRY

ELSEVIER SCI LTD

Año: 2011 vol. 125 p. 791 - 796

0308-8146

In this work, we have developed and characterised a novel microfluidic immunoassay methodology forrapid and sensitive quantification of ZEA in feedstuffs samples. The detection of ZEA was carried out usinga competitive direct immunoassay method based on the use of anti-ZEA monoclonal antibodies immobilizedon magnetic microspheres 3-aminopropyl-modified manipulated for an external remobilize magnets.The ZEA in feedstuffs sample is allowed to compete with ZEA-horseradish peroxidase (HPR)conjugated for the immobilized anti-ZEA antibody. The HPR, in the presence of hydrogen peroxide(H2O2) catalyses the oxidation of 4-tert-butylcatechol (4-TBC) whose back electrochemical reductionwas detected on gold electrode at 0.0 V. The calculated detection limits for electrochemical detectionand ELISA procedure were 0.41 and 2.56 lg kg1 respectively, the intra and inter-assay coefficients of variationwere below 6.5% and the total assay time was 30 min. The microfluidic immunosensor showedhigher sensitivity and lower detection limits than the standard ELISA method, which shows potentialfor detecting ZEA in foods and feeds diagnosis.