A Sensitive Method for the Rapid Determination of Underivatized Ethyl Carbamate in Fortified Wine by Liquid Chromatography-Electrospray Tandem Mass Spectrometry

Abstract

This work presents the optimization of a miniaturized liquid-liquid extraction (mLLE) followed by reversed-phase liquid chromatography-electrospray tandem mass spectrometry (RP-HPLC-MS/MS) for the determination of ethyl carbamate (EC) in fortified wine, without using derivatizing agents. The mLLE was optimized by an experimental design. Thus, 15 mL of wine and 8 mL of ethyl acetate were used for the extraction. After concentration, each extract was injected into the HPLC-MS/MS equipment and the characteristic secondary ion transition of EC (m/z = 90.10 → 62.05) was used for the quantification purposes. The proposed method presented a good linearity (R 2 = 0.9999) and a high sensitivity with low limits of detection (LOD) and quantification (LOQ), 0.17 and 0.52 μg L −1 , respectively. The precision (repeatability and reproducibility) never exceeded 8% of variation, and the recoveries varied between 93 and 114%. The applicability of the method was checked through the analysis of 24 fortified wines, with EC values ranging between 23 ± 1 and 194 ± 5 μg L −1 . All chromatograms revealed good peak resolutions. This new method is efficient for the simple, fast, and reliable determination of EC in fortified wines, providing great sensitivity without using derivatizing agents or large volumes of organic solvents.

New insights into ethyl carbamate occurrence in fortified wines

“…The quantification of EC in the studied samples was achieved applying the method proposed by Leça et al (2018), without any modification. EC present in model wines was concentrated by miniaturized liquid-liquid extraction with ethyl acetate as extraction solvent, separated from other extracted compounds by reversed-phase liquid chromatography (RP-HPLC), detected by electrospray tandem mass spectrometry (MS/MS) and quantified by internal standard calibration with butyl carbamate.…”

Impact of Indigenous Non-Saccharomyces Yeasts Isolated from Madeira Island Vineyards on the Formation of Ethyl Carbamate in the Aging of Fortified Wines

“…An in-house method was followed for the quantitative determination of EC formation, consisting of a miniaturized liquid-liquid extraction followed by reversed-phase liquid chromatography with detection by electrospray tandem mass spectrometry (RP-HPLC-MS/MS), as previously described in [26]. The extraction of samples (15 mL) was vortex assisted using 8 mL of ethyl acetate, followed by N 2 evaporation.…”

Mass Spectrometry for Analysis of Changes during Food Storage and Processing

“…63 In addition, a triple-quadrupole mass analyzer operated in MRM mode has been described for MS/ MS determination of ethyl carbamate in fortified wine using [M + H] + as the precursor ion and [M + H − C 2 H 4 ] + as the product ion. 64 In a recent study conducted by Ribeiro et al, direct-injection MS has been exploited for rapid quantitation of ethyl carbamate in sugar cane spirit. 65 The method used 8crown-6/trifluoroacetic acid as spiked additives to eliminate the sodiated ions [M + Na] + and potassiated ions [M + K] + of ethyl carbamate and improve the analytical signal of [M + H] + for preceding MS/MS quantification.…”