Determination of Ethyl Carbamate in Sugar Cane Spirit by Direct Injection Electrospray Ionization Tandem Mass Spectrometry Using 18-Crown-6/Trifluoroacetic Acid Spiking Additives

Abstract

In this work, we describe a 2-min direct injection electrospray tandem quadrupolar mass spectrometric method for ethyl carbamate (EC) detection in Brazilian sugar cane spirit (SCS). Analyses were carried out with 18-crown-6/trifluoracetic acid (30 ppm/0.1%) additives to sequester metal cations by eliminating unwanted [EC + Na]+ and [EC + K]+ ions, favoring analyte detection as sole [EC + H]+ ions. Standard addition of EC was carried out with 18-crown-6/trifluoracetic acid (30 ppm/0.1%), resulting in spiked SCS samples (0, 75, 150, 300, 450, 600, 750, and 900 μg L−1). A carrier solution of methanol:18-crown-6:trifluoroacetic acid (99.9:30 ppm:0.10, v/v/v) was pumped to the mass spectrometer using positive ion mode and multiple reaction monitoring of 90 > 62 for EC. The limits of detection and quantification were 7.5 and 75.0 μg L−1, respectively, and the dynamic range used was 75–900 μg L−1. The validation results and application of the method to the analysis of real samples and certified SCS demonstrate its applicability to quality control and regulatory analysis.