Selective determination of altertoxins by high-performance liquid chromatography with electrochemical detection with dual "in-series" electrodes.

A selective method for the determination of altertoxin-I and altertoxin-II by high-performance liquid chromatography with electrochemical detection is described. Altertoxins were separated on a reversed-phase column with methanol-water containing 0.1 M sodium nitrate and 1 mM nitric acid (60:40) as eluent and detected with dual in-series electrodes operating in the "redox" mode (generator electrode +1.0 V, indicator electrode -0.1 V). The method was applied successfully to the determination of sub-ppm levels of altertoxins in samples of maize, rice and tomatoes infected by Alternaria alternata.