Co-isolation of deoxynivalenol and zearalenone with sol-gel immunoaffinity columns for their determination in wheat and wheat products.
The paper describes a sample clean-up method for the co-isolation of deoxynivalenol (DON) and zearalenone (ZON), two mycotoxins naturally co-occurring in wheat. The method is based on immunoaffinity columns prepared by co-immobilising anti-DON and anti-ZON antibodies in a porous sol-gel glass. The main task in developing the method consisted in finding a loading medium allowing retention of both analytes as well as a common elution medium for the dissociation of both antigen-antibody complexes formed. This can be achieved by co-extracting DON and ZON with ACN-water (60:40, v/v), reducing the acetonitril concentration to 2.5% before loading an aliquot of the diluted sample extract onto the DON/ZON column. The columns are washed with 5 ml of MeOH-water (10:90, v/v) before DON and ZON are co-eluted with 4 ml of ACN-water (50:50, v/v). Concentrations of DON and ZON are determined with HPLC-UV and HPLC-fluorescence detection, respectively. The sample clean-up method was shown to be applicable to wheat and wheat products, e.g., cornflakes, milk wheat mash and rusk. Spiking experiments (spike level 500 microg DON/kg and 50 microg ZON/kg) resulted in recovery rates from 82% to 111%.
Brenn-Struckhofova
Zdenka
Z
Department of Analytical and Food Chemistry, University of Vienna, Währinger Strasse 38, A-1090 Vienna, Austria.
Füreder
Christa
C
Cichna-Markl
Margit
M
Razzazi-Fazeli
Ebrahim
E
D000906:Antibodies / Q000737:chemistry; D002846:Chromatography, Affinity / Q000379:methods*; D005504:Food Analysis / Q000379:methods; D016014:Linear Models; D044367:Phase Transition; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014255:Trichothecenes / Q000302:isolation & purification*; D014908:Triticum / Q000737:chemistry*; D015025:Zearalenone / Q000302:isolation & purification*
D000906:Antibodies; D014255:Trichothecenes; D015025:Zearalenone; C007262:deoxynivalenol