An HPLC-MS/MS Method Using a Multitoxin Clean up Column for Analysis of Seven Mycotoxins in Aquafeeds

In Guangdong Province of China, the climate is very wet, so there are many different fungi living in aquatic feeds, which produce mycotoxins. These compounds contaminate agricultural products worldwide and present a great threat to human health. It is necessary to determine their contamination level in aquatic feeds.

A high performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS) method was developed for the quantitative analysis of aflatoxin B1, aflatoxin M1, T-2 toxin, HT-2 toxin, deoxynivalenol, ochratoxin, and zearalenone in fish and shrimp feed.

Samples were extracted with acetonitrile-water (3+1, v/v), and degreased with acetonitrile-saturated hexane. The extract was cleaned up with a multitoxin column. The target compounds were separated on a C18 chromatographic column and analyzed simultaneously by electrospray ionization mass spectrometry in both positive and negative ion mode. Detected compounds were quantified using the matrix-matched external standard method.

Under the optimized conditions, good linearities for the analytes in the corresponding concentration range were obtained, with correlation coefficients (r2) higher than 0.9948. LODs ranged from 1.83 to 12.63 μg/kg, and LOQs ranged from 5.49 to 37.89 μg/kg. Average recoveries for the target mycotoxins at three spiked levels ranged from 80.5 to 116.5% with RSD ranging from 2.4 to 10.4%. Twenty-three real aquafeed samples were determined by this method, and seven kinds of toxins were detected.

The results show that the developed method can be successfully applied for the simultaneous determination of mycotoxins in aquatic feeds.

Multitoxin purification columns proved to be a powerful technique for determining seven mycotoxins simultaneously. This method ensured simple sample pretreatment and less operation time. The established method was successfully applied to the analysis of seven mycotoxins species in aquatic feeds.