Wang Ting-Ting, Chen Yi-Hui, Ma Jun-Feng, Hu Min-Jie, Li Ying, Fang Jiang-Hua, Gao Hao-Qi
College of Chemical Engineering, Ningbo University of Technology, Ningbo, 315016, China,
Anal Bioanal Chem. 2014 Aug;406(20):4955-63. doi: 10.1007/s00216-014-7923-4. Epub 2014 Jun 18.
A novel ionic liquid-modified organic-polymer monolithic capillary column was prepared and used for in-tube solid-phase microextraction (SPME) of acidic food additives. The primary amino group of 1-aminopropyl-3-methylimidazolium chloride was reacted with the epoxide group of glycidyl methacrylate. The as-prepared new monomer was then copolymerized in situ with acrylamide and N,N'-methylenebisacrylamide in the presence of polyethylene glycol (PEG)-8000 and PEG-10,000 as porogens. The extraction performance of the developed monolithic sorbent was evaluated for benzoic acid, 3-hydroxybenzoic acid, cinnamic acid, 2,4-dichlorophenoxyacetic acid, and 3-(trifluoromethyl)-cinnamic acid. Such a sorbent, bearing hydrophobic and anion-exchange groups, had high extraction efficiency towards the test compounds. The adsorption capacities for the analytes dissolved in water ranged from 0.18 to 1.74 μg cm(-1). Good linear calibration curves (R(2) > 0.99) were obtained, and the limits of detection (S/N = 3) for the analytes were found to be in the range 1.2-13.5 ng mL(-1). The recoveries of five acidic food additives spiked in Coca-Cola beverage samples ranged from 85.4 % to 98.3 %, with RSD less than 6.9 %. The excellent applicability of the ionic liquid (IL)-modified monolithic column was further tested by the determination of benzoic acid content in Sprite samples, further illustrating its good potential for analyzing food additives in complex samples.
制备了一种新型离子液体改性的有机聚合物整体毛细管柱，并将其用于酸性食品添加剂的管内固相微萃取（SPME）。1-氨丙基-3-甲基咪唑氯盐的伯氨基与甲基丙烯酸缩水甘油酯的环氧基发生反应。然后，将制备好的新单体与丙烯酰胺和N,N'-亚甲基双丙烯酰胺在聚乙二醇（PEG）-8000和PEG-10,000作为致孔剂的存在下原位共聚。评估了所开发的整体吸附剂对苯甲酸、3-羟基苯甲酸、肉桂酸、2,4-二氯苯氧乙酸和3-（三氟甲基）肉桂酸的萃取性能。这种带有疏水基团和阴离子交换基团的吸附剂对测试化合物具有较高的萃取效率。对溶解在水中的分析物的吸附容量范围为0.18至1.74 μg cm(-1)。获得了良好的线性校准曲线（R(2) > 0.99），分析物的检测限（S/N = 3）在1.2 - 13.5 ng mL(-1)范围内。在可口可乐饮料样品中添加的五种酸性食品添加剂的回收率范围为85.4%至98.3%，相对标准偏差小于6.9%。通过测定雪碧样品中的苯甲酸含量，进一步测试了离子液体（IL）改性整体柱的优异适用性，进一步说明了其在分析复杂样品中的食品添加剂方面的良好潜力。
