title: Analysis of Mycotoxins in Beer Using a Portable Nanostructured Imaging Surface Plasmon Resonance Biosensor.
abstract: A competitive inhibition immunoassay is described for the mycotoxins deoxynivalenol (DON) and ochratoxin A (OTA) in beer using a portable nanostructured imaging surface plasmon resonance (iSPR) biosensor, also referred to as imaging nanoplasmonics. The toxins were directly and covalently immobilized on a 3-dimensional carboxymethylated dextran (CMD) layer on a nanostructured iSPR chip. The assay is based on competition between the immobilized mycotoxins and free mycotoxins in the solution for binding to specific antibodies. The chip surface was regenerated after each cycle, and the combination of CMD and direct immobilization of toxins allowed the chips to be used for more than 450 cycles. The limits of detection (LODs) in beer were 17 ng/mL for DON and 7 ng/mL for OTA (or 0.09 ng/mL after 75 times enrichment). These LODs allowed detection of even less than 10% depletion of the tolerable daily intake of DON and OTA by beer. Significant cross-reactivity of anti-DON was observed toward DON-3-glucoside and 3-acetyl-DON, while no cross-reactivity was seen for 15-acetyl-DON. A preliminary in-house validation with 20 different batches of beer showed that both toxins can be detected at the considered theoretical safe level for beer. The assay can be used for in-field or at-line detection of DON in beer and also in barley without preconcentration, while OTA in beer requires an additional enrichment step, thus making the latter in its present form less suitable for field applications.
authors.affiliation: Laboratory of Organic Chemistry, Wageningen University , Stippeneng 4, 6708 WE Wageningen, The Netherlands.|TI-COAST , Science Park 904, 1098 XH Amsterdam, The Netherlands.
authors.forename: Sweccha
authors.initials: S
authors.lastname: Joshi
authors.affiliation: Laboratory of Organic Chemistry, Wageningen University , Stippeneng 4, 6708 WE Wageningen, The Netherlands.
authors.forename: Rumaisha M
authors.initials: RM
authors.lastname: Annida
authors.affiliation: Laboratory of Organic Chemistry, Wageningen University , Stippeneng 4, 6708 WE Wageningen, The Netherlands.
authors.forename: Han
authors.initials: H
authors.lastname: Zuilhof
authors.affiliation: Laboratory of Organic Chemistry, Wageningen University , Stippeneng 4, 6708 WE Wageningen, The Netherlands.
authors.forename: Teris A
authors.initials: TA
authors.lastname: van Beek
authors.affiliation: Laboratory of Organic Chemistry, Wageningen University , Stippeneng 4, 6708 WE Wageningen, The Netherlands.|RIKILT Wageningen University & Research , P.O. Box 230, 6700 AE, Wageningen, The Netherlands.
authors.forename: Michel W F
authors.initials: MW
authors.lastname: Nielen
mesh_terms: D001515:Beer / Q000032:analysis*; D015374:Biosensing Techniques; D002138:Calibration; D005504:Food Analysis / Q000295:instrumentation / Q000379:methods; D005506:Food Contamination / Q000032:analysis*; D001467:Hordeum; D057230:Limit of Detection; D009183:Mycotoxins / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D049329:Nanostructures; D009793:Ochratoxins / Q000032:analysis / Q000378:metabolism; D015203:Reproducibility of Results; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods*; D014255:Trichothecenes / Q000032:analysis / Q000378:metabolism
chemical_list: D009183:Mycotoxins; D009793:Ochratoxins; D014255:Trichothecenes; C025589:ochratoxin A; C007262:deoxynivalenol
keywords: beer; deoxynivalenol; imaging SPR; mycotoxins; nanoplasmonics; ochratoxin A