Analysis of ochratoxin A in pig tissues using high pressure liquid chromatography (HPLC) and liquid chromatography tandem mass spectrometry (LC/MS/MS) as confirmative methods

Abstract

Two different analytical methods for the determination and confirmation of ochratoxin A (OTA) in blood serum, kidney and liver of pigs have been compared. Sample clean-up was based on liquid-liquid phase extraction. The detection of OTA was accomplished with high-performance liquid chromatography (HPLC) combined either with fluorescence detection (FL) or electro spray ionization (ESI+) tandem mass spectrometry (MS-MS). Comparative method evaluation was based on the investigation of 82 samples of blood serum, kidney and liver originating from different regions of Serbia. The analytical results are discussed in view of the respective method validation data and the corresponding experimental protocols. In general, analytical data obtained with LC-MS-MS detection offered comparably good results in the sub-ppb concentration level indicating that the liquid chromatography electro spray tandem mass spectrometric (LC-MS/MS) method was more specific and sensitive for the analysis and confirmation of ochratoxin A in pig tissues than high pressure liquid chromatography (HPLC) method after methylation of OTA.U ovom radu prikazani su rezultati poredjenja dve analiticke tehnike za odredjivanje prisustva i konfirmaciju rezidua ohratoksina A (OTA) u krvnoj plazmi, jetri i bubrezima svinja. Preciscavanje ekstrakta izvrseno je po metodi za tecno-tecnu ekstrakciju, a za detekciju OTA koriscena je visokoefikasna tecna hromatografija sa fluorescentnim detektorom (HPLC-FL) i tecna hromatografija sa masenom spektrometrijom (LC-MS/MS). Poredjenje metoda izvrseno je na osnovu analize 82 uzorka krvne plazme, jetre i bubrega svinja, poreklom sa razlicitih lokaliteta Srbije. Dobijeni rezultati su tumaceni shodno metodologiji predvidjenoj za validaciju, a na osnovu odgovarajuceg laboratorijskog protokola. Na osnovu dobijenih rezultata moze se zakljuciti da su upotrebom tecne hromatografije sa masenom spektrometrijom (LC-MS/MS) detektovane vrlo niske koncentracije OTA (sub ppb), sto ukazuje da je LC-MS/MS tehnika mnogo specificnija i senzitivnija za odredjivanje prisustva i konfirmaciju OTA u tkivima svinja, u odnosu na uobicajeni derivatizacioni postupak upotrebom HPLC-FL tehnike.