Analytical Sciences


Abstract − Analytical Sciences, 34(2), 221 (2018).

Detection and Quantification of 4-Methylimidazole in Cola by Matrix-assisted Laser Desorption Ionization Mass Spectrometry with Fe2O3 Nanoparticles on Zeolite
Yosuke FUJII,*1 Yuqi DING,*2 Taichi UMEZAWA,*3 Takafumi AKIMOTO,*1 Jiawei XU,*1 Takashi UCHIDA,*4 and Tatsuya FUJINO*3,*4
*1 Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo 192-0379, Japan
*2 Department of Food Inspection, Zhejiang Institute for Food and Drug Control, No. 86, Lane 1, Jichang Road, Jianggan District, Hangzhou, Zhejiang, China
*3 Department of Applied Chemistry, Graduate School of Science and Engineering, Toyo University, 2100 Kujirai, Kawagoe 350-8585, Japan
*4 Bio-Nano Electronics Research Centre, Toyo University, 2100 Kujirai, Kawagoe 350-8585, Japan
Food additives generally used in carbonated drinks, such as 4-methylimidazole (4MI), caffeine (Caf ), citric acid (CA), and aspartame (Apm), were measured by matrix-assisted laser desorption ionization mass spectrometry (MALDI MS) using nanometer-sized particles of iron oxide (Fe2O3 NPs). The quantification of 4MI in Coca Cola (C-cola) was carried out. In order to improve the reproducibility of the peak intensities, Fe2O3 NPs loaded on ZSM5 zeolite were used as the matrix for quantification. By using 2-ethylimidazole (2EI) as the internal standard, the amount of 4MI in C-cola was determined to range from 88 to 65 μg/355 mL. The results agree with the published value (approx. 72 μg/355 mL). It was found that MALDI using Fe2O3 was applicable to the quantification of 4MI in C-cola.