An Improved HPLC Procedure for Domoic Acid Analysis in Seafood

A high performance liquid chromatographic (HPLC) procedure was developed for the determination of domoic acid (DA) in seafood, including on-line sample purification. Unpurified aqueous methanol extracts of tissue samples were partially purified with a cyano precolumn cartridge. Separation was performed on a reverse-phase C-18 column with gradient elution, and UV detection. UV spectra were acquired for confirmation. Analyte recoveries from 89% to 100% were obtained for a variety of tissues. The detection limit with confirmation by UV spectrum was 0.1 μg/g. The method eliminates the use of a manual sample cleanup step. In contrast to other published procedures, the method is insensitive to NaCl, which maybe present at high concentrations in some seafood samples. Further, tryptophan does not interfere.