Detection of Aflatoxins in Milk at Picogram Levels Using SPE and LC-MS/MS

This application note outlines a method for the low level determination of aflatoxins in milk using a polymeric solid-phase extraction (SPE) cartridge. Analysis is performed by LC-MS/MS using a Selectra® DA HPLC column. Aflatoxins are naturally occurring mycotoxins that are produced by several species of fungi (Aspergillus flavus and Aspergillus parasiticus). There are approximately 20 related aflatoxin metabolites, although only B1, B2, G1 and G2 are normally found in food. Of these, aflatoxin B1 is the most biologically active and aflatoxins can occur in milk as a result of dairy animals consuming contaminated feed. The main residue of concern in milk is aflatoxin M1, the major metabolite of B1. The intake of contaminated milk, even at low concentrations, is a significant threat to human health, especially to children who are a major consumer of dairy products.