US EPA

5932994 

Journal Article 

Direct injection gas chromatographic mass spectrometric analysis for denatonium benzoate in specific denatures alcohol formulations 

Ng, LK; Hupe, M; Harnois, J; Lawrence, AH 

1998 

Yes 

Analytical Chemistry
ISSN: 0003-2700
EISSN: 1520-6882 

American Chemical Society 

WASHINGTON 

70 

20 

4389-4393 

English 

10.1021/ac980093r 

WOS:000076487800025 

Direct injection GC/MS was investigated for the analysis of benzyldiethyl(2,6-xylylcarbamoylmethyl)ammonium benzoate (Bitrex), a quaternary ammonium salt, in various Canadian denatured alcohol formulations. Bitrex yielded predominantly a peak due to the neutral diethylamine derivative(I). The structure of I, elucidated by MS and NMR, is strongly related to that of the cation of Bitrex, Compound I was formed from Bitrex in the heated injector port of the GC via a decomposition reaction similar to Stevens rearrangement. The response of I was found to be dependent on the injector port temperature, and the optimal temperature was determined to be in the range 250-350 degrees C. The GC/MS response of I in SIM mode was used to quantify Bitrex, The effects of the codenaturants sucrose octaacetate (SOA), diethyl phthalate (DEP), and camphor, which are present at much higher concentration than Bitrex in several formulations, were also investigated. The presence of SOA enhanced the response of the analyte considerably, while DEP and camphor had no significant effect. All standard curves of Bitrex (1-16 ppm) in different alcohol matrixes were fitted by second-order polynomial functions, with coefficients of determination (R-2) routinely in the range 0.998-0.999. The analysis time was 18 min, and the within-run precision was <4%. The results of this study point to the potential of the GC/MS technique as a quantitative tool for Bitrex in various alcohol formulations.