Department of Analytical Chemistry and Research Institute on Water, Climate Change and Sustainability (IACYS), University of Extremadura, 06006 Badajoz, Spain.
Department of Analytical Chemistry and Research Institute on Water, Climate Change and Sustainability (IACYS), University of Extremadura, 06006 Badajoz, Spain.
Talanta. 2017 Jun 1;168:100-104. doi: 10.1016/j.talanta.2017.03.031. Epub 2017 Mar 11.
Carbonyl compounds, like glyoxal, methylglyoxal, diacetyl or pentane-2,3-dione, among others, have been widely studied. Besides its endogenous origin, they are originated from foodstuffs and are related to sensorial characteristics in products such as wine and beer. Generally, for their determination, the analytes must be derivatised to adapt them for the detection system and this step takes long time. The main aim of this research was to develop a simultaneous derivatization and extraction method which takes place in only few minutes. 3,4-diaminopyridine, as derivatizing reagent, generate a fluorescent product. This reaction is selective for glyoxal. For this new dispersive liquid-liquid microextraction (DLLME) procedure combined with chromatographic determination of glyoxal, various parameters affecting the extraction were optimized and finally, a mixture of butan-1-ol as dispersant solvent and dichloromethane as extractant solvent were selected. Its chromatographic peak appears at 2.6min. Four Spanish wines and five Spanish beers have been analysed and the results showed that the levels of glyoxal are comprised between 2.8-9.5mgL. The proposed DLLME method drastically reduces the reaction time from 2 or 3-20min improving the methods found in the literature. The glyoxal concentration found in the wines and beers analysed do not suppose any health risk.
羰基化合物，如乙二醛、甲基乙二醛、双乙酰或 2,3-戊二酮等，已经得到了广泛的研究。除了内源性来源外，它们还来源于食品，并与葡萄酒和啤酒等产品的感官特性有关。通常，为了测定它们，分析物必须衍生化以适应检测系统，这一步需要很长时间。本研究的主要目的是开发一种仅需几分钟即可同时进行衍生化和提取的方法。3,4-二氨基吡啶作为衍生化试剂，生成一种荧光产物。该反应对乙二醛具有选择性。对于这种新的分散液-液微萃取（DLLME）与乙二醛色谱测定相结合的方法，优化了影响萃取的各种参数，最终选择了丁醇-1 作为分散溶剂和二氯甲烷作为萃取溶剂的混合物。其色谱峰出现在 2.6min。对四种西班牙葡萄酒和五种西班牙啤酒进行了分析，结果表明乙二醛的含量在 2.8-9.5mgL 之间。与文献中发现的方法相比，所提出的 DLLME 方法大大缩短了反应时间（从 2 或 3-20min）。所分析的葡萄酒和啤酒中的乙二醛浓度不存在任何健康风险。
