Determination of patulin by online-SPE-LC

The mycotoxin patulin mainly occurs in fruits and fruit-derived products. For its determination a newly developed method employing a simplified liquid-liquid partitioning step followed by an online-SPE-LC analysis with UV detection is presented. The sample is diluted with phosphate buffer and extracted with ethyl acetate. The extract is evaporated and re-dissolved. The online-SPE-LC analysis employs a styrene-divinylbenzene copolymere phase for the SPE step, on which the carbonate washing step is carried out as well. The final LC analysis with UV detection uses a Polaris C18A column. This method reaches a limit of quantification of 15 μg/kg (clear apple juice), with a standard deviation of 10.7% (matrix calibration, n=5; c (patulin)=50 μg/kg).