Liu Jing-Fu, Peng Jin-Feng, Chi Yu-Guang, Jiang Gui-Bin
Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, PR China.
Talanta. 2005 Feb 15;65(3):705-9. doi: 10.1016/j.talanta.2004.07.037.
Using ionic liquid as extraction solvent and 2,4-dinitrophenylhydrazine (DNPH) as derivative agent, formaldehyde in shiitake mushroom was determined by liquid-phase microextraction coupled with high-performance liquid chromatography (HPLC). Shiitake mushroom was leached with water and filtrated, then the formaldehyde in filtrate was derivatized with DNPH and extracted simultaneously into a 10mul drop of ionic liquid suspended on the tip of the microsyringe, and finally injected into the HPLC system for determination. The proposed procedure has a detection limit of 5mugl(-1) formaldehyde in extraction solution, thus the mushroom sample filtrate could be diluted with a large ratio to eliminate the influence of sample matrix. The method has a relative standard deviation of 3.5% between days for 53.5mugl(-1) formaldehyde standards. High contents of formaldehyde (119-494mugg(-1) wet weight), which is harmful for human beings, were detected in shiitake mushroom. Therefore, strategies must be taken to prevent the accumulation and strictly control the content of formaldehyde in shiitake mushroom.
以离子液体为萃取溶剂，2,4 -二硝基苯肼（DNPH）为衍生剂，采用液相微萃取 - 高效液相色谱法（HPLC）测定香菇中的甲醛。香菇用水浸提并过滤，滤液中的甲醛用DNPH衍生化，同时萃取到悬浮于微量注射器针尖的10微升离子液体滴中，最后注入HPLC系统进行测定。该方法对萃取液中甲醛的检测限为5微克/升，因此香菇样品滤液可大幅稀释以消除样品基质的影响。对于53.5微克/升的甲醛标准溶液，该方法日间相对标准偏差为3.5%。在香菇中检测到了高含量（119 - 494微克/克湿重）对人体有害的甲醛。因此，必须采取策略防止甲醛积累并严格控制香菇中甲醛的含量。
