Quantification of three furfurals in food using a triazine-based hydrazine derivatization reagent by MALDI mass spectrometry

In this study, a high-throughput matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) method was developed for detecting three furfurals (furfural, 5-methylfurfural, and 5-hydroxymethylfurfural) in food. The derivatization of furfurals with 4-dimethylamino-6-(4-methoxy-1-naphthyl)-1,3,5-triazine-2-hydrazine (DMNTH) resulted in a substantial increase in the m/z values of furfurals and an improvement in detection sensitivity. The compound 5-methoxymethylfurfural, a structural analogue of furfurals, was utilized as an internal standard to correct for fluctuations in mass spectrometry signals and matrix effects present in the real samples. The calibration curves exhibited good linearity in the furfural concentration range of 0.5–50 μg/mL, with correlation coefficients (R) exceeding 0.9996. The limits of quantification were in the range of 0.20–0.39 μg/mL. The furfural recoveries ranged from 89.2% to 116.2%, and the intra- and inter-day precisions were less than 10.8%, indicating high detection accuracy and precision. The developed method was successfully applied to the detection of furfurals in a variety of real samples, including roasted coffee beans, honey, and vinegar. The results demonstrated that the developed method was rapid and high-throughput, meeting the requirements for accurately detecting furfurals in various foods.