A simple GC-MS method has been developed and validated for the direct determination of hexamethylenetetramine (HMT). The separation of HMT was performed using a MXT-1 column. The calibration curve was linear over the concentration range 0.1-25 μg/mL, with a good correlation coefficient (r =0.9996). The recoveries of HMT from foods spiked at 1, 5, and 10 μg/g ranged from 91.7% to 115.2%. Intra-day (n=5) and inter-day (n=5) precision were less than 7%. The limit of detection and the limit of quantification of the method were 0.05 and 0.15 μg/mL, respectively. The uncertainties associated with food matrix and calibration contributed most to the overall expanded uncertainty. The method validation data indicated that quantitative method could be applied to the direct determination of non-hydrolyzed HMT in foods.
Keywords: direct determination; gas chromatography-mass spectrometry; hexamethylenetetramine; method validation.