Determination of ethyl carbamate in spirits using salting-out assisted liquid-liquid extraction and high performance liquid chromatography with fluorimetric detection

In this work, a simple methodology was developed for the determination of ethyl carbamate (EC) in spirits by high performance liquid chromatography with fluorimetric detection. The sample is subjected to salting-out assisted liquid-liquid extraction (SALLE) using a 9-xanthydrol/acetonitrile solution for the simultaneous extraction and derivatisation of EC. Extraction/derivatization occurs under acidic conditions (0.5 mol L-1 HCl) and NaCl was used for phase separation. The methodology showed low limits of detection and quantification (9 mu g L-1 and 23 mu g L-1, respectively) and good precision (4.4% intraday and 8.7% interday). The determined EC concentrations in the analysed samples varied between 51 and 266 mu g L-1. The proposed sample preparation methodology is simple and low cost, it uses limited toxicity solvents and the obtained extract is readily compatible with reversed phase liquid chromatography. Moreover, the stability of the xanthyl-EC product was verified. More importantly it is a more robust alternative to the liquid chromatography based methodologies that do not apply any extraction procedure, which do not consider the problems associated with the long term deterioration of the analytical systems.