Analysis of Ethyl Carbamate in Wines Using Solid-Phase Extraction and Multidimensional Gas Chromatography/Mass Spectrometry

Abstract

The method describes a rapid and accurate procedure for the analysis of ethyl carbamate in wines. The separation of the ethyl carbamate (EC), the target analyte, from alcohol and the sample matrix is a challenge to many analytical chemists. After alcohol removal from the sample, EC was extracted and concentrated by solid-phase extraction. For analysis of EC, large-volume injection on a programmable temperature vaporization (PTV) inlet was used followed by multidimensional gas chromatography/mass spectrometry (MDGC/MS) using electron-impact ionization (EI). For quantitation, the ratio of ions produced during EI at m/z 62 (EC) and 64 (isotopically labeled EC) was monitored. The use of solid-phase extraction and MDGC/MS removes the majority of the matrix interference encountered in other methods. A linear dynamic range was established from 0.387 to 1160 ng/mL, with a limit of detection at 0.1 ng/mL and limit of quantitation at 1 ng/mL.

Comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry combined with solid phase microextraction as a powerful tool for quantification of ethyl carbamate in fortified wines. The case study of Madeira wine

“…These high values may be explained to the fact that stone-fruit spirits contain considerably higher levels of EC (in the mg/L range) and also contain much higher levels of alcohol, which interfere with SPME extraction, so that the samples have to be diluted. Furthermore, lower LOD and LOQ values (0.1 and 1 g/L) were achieved by Jagerdeo et al [7] to quantify EC table wines using SPE/LVI-MDGC-MS (solid phase extraction/large volume injectionmultidimensional gas chromatography-mass spectrometry). This MDGC-MS is composed by two gas chromatographs and a mass spectrometer that allowed heart-cutting peaks of interest and disposal of the unwanted portion of the chromatogram.…”

“…Nevertheless, not all nitrogen-containing compounds show the same kinetics when reacting with ethanol. For example, it has been demonstrated that EC formation from urea (which results from the degradation of arginine by yeasts) increases dramatically with temperature (for example in baking, boil- ing or toasting processes) [3,6,7], and more rapidly than from citrulline [8].…”

“…Several extraction methodologies have been used, such as continuous liquid-liquid extraction [13], and solid phase extraction [7,14,15], combined with one-dimensional gas chromatography coupled with mass spectrometry detection (GC-MS). EC has been determined in fortified Madeira wines by SPE followed by GC-MS [15,16], and by derivatization with 9-xanthydrol, followed by high performance liquid chromatography (HPLC) [17].…”

“…The extraction step is followed mainly by GC-MS analysis [7,13,15,16]. To achieve the adequate sensitivity for EC detection, an injector equipped with a unit for large volume injection [7], or MS-SIM (selected ion monitoring) [13,19] or MS-MS acquisition modes (GC-MS-MS) [9,14,21] were used. Onedimensional chromatographic processes are widely applied in the analysis of food products.…”

Ultra-Trace Determination of Methyl Carbamate and Ethyl Carbamate in Local Wines by GC-FID Following Pre concentration with C18-SPE

“…Most of the reported methods for ethyl carbamate analysis employ solid-phase extraction, liquidliquid extraction and preconcentration prior to gas chromatographic separation 21,22 . Some methods still include an additional extraction cleanup step 4,15 . Ethyl carbamate detection is usually performed by mass spectrometry [1][2][3][4]7,8,15 , either on electron or chemical ionization 23,24 .…”