Abstract: A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was proposed to determine ochratoxin A (OTA) in foods. Samples were extracted by methanol-2% sodium bicarbonate solution (60:40, V/V) or methanol-water (80:20, V/V), followed by clean-up on OchraTest affinity cartridge using methanol-5 mmol/L ammonium acetate solution in the presence of 0.1% formic acid as the mobile phase. OTA was detected in the in positive ion mode. The average spike recoveries for ochratoxin A in 4 food samples were 82.3%－ 98.5% (n ＝5). The limit of detection was 0.1 μg/kg, which can meet the latest requirement of the EU. Moreover, this method proved suitable for a broad range of sample matrices with high accuracy, sensitivity and disturb resistance.

Key words: high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), ochratoxin A, immuno-affinity column, multiple reaction monitoring (MRM)