Comparison of two different clean - up procdures for liquid chrom atographic determination of ochratoxin A in raisin

1Department of Natural Resources and medicinal plants, Agriculture center for Higher Education,Agricultural Research and Education Organization. Karaj2Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences.PO Box 13145-784. Tehran, IranIn this study, two different procedures; one using immunoaffinity clean – up and anotherusing mycosep clean- up columns were used. The immunoaffinity and mycosep columnsused in our study were Ochra Test; Ochraprep and the new mycosep 229 ochrarespectively. In all procedures, separations were carried out by high performance liquidchromatography and fluorescence detection. The mean recovery of OTA using theprocedure with mycosep column at spiking level of 30 and 40 µg/kg were 65.1 % with aRSD 11.92 % and 84.52 % with a RSD 9.97 % respectively. The mean recovery of OTAin the other procedures with raisin samples purified on immunoaffinity column in spikinglevels; 7.5, 10, 15, 20 and 25 µg/kg varied from 50.96 % to 100.08 % with the RSDranged 5.35% to 36.43%. The limit of detection for the method of ochratoxin A in rasinpurified with mycosep and immunoaffinity column were 20 and 5 µg/kg, respectively.