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.

Recent advances of in-tube solid-phase microextraction

“…More recently, the use of ionic liquids (ILs), as green solvents, as functional monomers to prepare an organic polymer monolithic capillary column for in-tube SPME was reported by Wang et al [54]. This new extractive phase was successfully applied to determine antimicrobial food additives.…”

Determination of Sudan Dyes in Juice Samples via Solidification of Ionic Liquid in Microwave-Assisted Liquid-Liquid Microextraction Followed by High-Performance Liquid Chromatography

“…As an environmentally friendly solvent, the room temperature ionic liquids (RTILs) are semiorganic salts, with important features including high viscosity, low vapor pressure, good thermal stability, a wide range of miscibility with water and other organic solvents, nonflammability, and dual natural polarity (Poole and Poole 2010;Ravelo-Pérez et al 2009). Ionic liquid (IL) has been applied in LPME (Wang et al 2013a), SPME (Wang et al 2014), and aqueous two-phase systems extraction (Yu et al 2015). Furthermore, IL could also be a good alternative to traditional organic solvents in dispersive liquid-liquid microextraction.…”

Recent advances and future trends in new materials for sample preparation

“…The results showed high extraction efficiencies with recoveries of 85.4-98.3% for five acidic analytes. This could be obtained due to the uniform, small sizes of the particles that provided a large surface area for the adsorption of analytes and the existence of sorbent in mixed-mode interactions, such as anion exchange and hydrophobic [83].…”