On the other hand, since the determination of mycotoxins belongs to trace analysis, sample clean-up and pre-concentration steps are necessary to remove matrix components and enhance sensitivity prior to chromatographic analysis. Generally, sample pretreatment for the determination of OTA mainly involves liquide liquid extraction (LLE) and solid-phase extraction (SPE), the latter being preferred due to simplicity in operation and saving solvent requirements. Homemade and commercially available SPE cartridges with different kinds of bonding phases such as
silica-kieselguhr , OASIS HLB, ionexchange and immunoaffinity, have already been applied to the pretreatment for decades.