Analysis of heterocyclic amines in chicken by liquid chromatography with electrochemical detection

Abstract

The present paper describes a method based on liquid chromatography with electrochemical detection (LC–ECD) for the determination of heterocyclic amines (HAs) in food samples. In order to obtain extracts clean enough to quantify heterocyclic amines by liquid chromatography with electrochemical detection, an additional purification step based on a cationic exchanger (CBA) as sorbent was included in a clean-up performed by several solid-phase extraction steps. Two different mobile phases, acetonitrile–50 mM ammonium acetate (10:90) at pH 5.25, and acetonitrile–50 mM ammonium acetate (30:70) at pH 6.0, were used for the LC separation of polar and less polar amines. Optimum working potentials were +1000 and +950 mV for polar and less polar HAs, respectively. The obtained figures of merit showed detection limits of 5–79 pg for standards, 2–30 ng g −1 for beef extract and 0.3–2.9 ng g −1 for fried chicken sample, and day-to-day precisions of 1.2–7.6% for standards and 2.8–10.4% for fried chicken sample. The applicability of the LC–ECD method has been demonstrated by the determination of the amines in griddled and fried chicken.