title: A novel ionic liquid-modified organic-polymer monolith as the sorbent for in-tube solid-phase microextraction of acidic food additives.
abstract: 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.
authors.affiliation: College of Chemical Engineering, Ningbo University of Technology, Ningbo, 315016, China, shiming-49@163.com.
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Wang
authors.forename: Yi-Hui
authors.initials: YH
authors.lastname: Chen
authors.forename: Jun-Feng
authors.initials: JF
authors.lastname: Ma
authors.forename: Min-Jie
authors.initials: MJ
authors.lastname: Hu
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.forename: Jiang-Hua
authors.initials: JH
authors.lastname: Fang
authors.forename: Hao-Qi
authors.initials: HQ
authors.lastname: Gao
mesh_terms: D019817:Benzoic Acid / Q000032:analysis* / Q000302:isolation & purification; D001628:Beverages / Q000032:analysis*; D005503:Food Additives / Q000737:chemistry*; D005504:Food Analysis / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D052578:Ionic Liquids; D009930:Organic Chemicals / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D052617:Solid Phase Microextraction / Q000379:methods*
chemical_list: D005503:Food Additives; D052578:Ionic Liquids; D009930:Organic Chemicals; D011108:Polymers; D011092:Polyethylene Glycols; D019817:Benzoic Acid