Development and validation of a HPLC method for the quantitation of ochratoxins in plasma and raw milk.
A HPLC method with improved sensitivity for the determination of ochratoxins (OT) A, B and alpha in plasma and milk was developed. Plasma analysis involved a simple liquid-liquid extraction with chloroform; while for milk, an additional immunoaffinity clean-up step was necessary. The method showed a good linearity (r(2)>0.999). The limit of quantification (LOQ) of OTA was 5 and 200 ng/l for milk and plasma, respectively. Average recovery was 89% in both matrices, except for OTalpha in milk that was only 18% due to poor immunoaffinity binding. OT remained stable in -20 degrees C stored samples; OTA concentration in plasma and milk did not change after 8 and 18 months of storage, respectively. The developed method has been applied to contaminated plasma and milk samples obtained from dairy ewes fed with ochratoxin-contaminated feed.
Boudra
H
H
French Institute for Agricultural Research (INRA), Clermont-Fd-Theix Research Centre, Herbivore Research Unit, 63122 Saint Genès-Champanelle, France. hboudra@clermont.inra.fr
Morgavi
D P
DP
D000821:Animal Feed / Q000032:analysis; D000818:Animals; D005260:Female; D005506:Food Contamination / Q000032:analysis; D008892:Milk / Q000737:chemistry*; D009793:Ochratoxins / Q000032:analysis* / Q000097:blood; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012756:Sheep
D009793:Ochratoxins