Preparation and application of immobilised ionic liquid in solid-phase extraction for determination of trace...

Acrylamide has attracted worldwide concerns because of its demonstrated neurotoxicity, genetoxicity and reproductive-development toxicity. It is necessary to control acrylamide production during food processing and protect human health.

In this study, a functionalised material was synthesised by immobilising an ionic liquid onto an activated silica gel surface. The adsorption ability of the material towards acrylamide was evaluated, and the results showed that it had high adsorption capacity. Scatchard analysis indicated that the binding sites in the prepared material had two distinct groups (high and low affinity binding sites). The saturated adsorption capacity (Q(max,1)) was 7.9 mg g(-1) due to the high affinity binding sites, and another saturated adsorption capacity (Q(max,2)) was 2.3 mg g(-1) due to the low affinity binding sites. This prepared material also offered fast kinetics for adsorption of the acrylamide. Using this material as sorbent, a method of solid-phase extraction coupled with high-performance liquid chromatography (SPE-HPLC) for analysis of acrylamide in foods was developed. Under optimal conditions, the limit of detection (S/N = 3) of this method for acrylamide was 2.1 µg kg(-1), and the RSD for five replicate extractions of 50 μL(-1) acrylamide was 4.5%. The blank potato and bread crumb samples spiked with acrylamide at different levels of 10.0 and 15.0 µg kg(-1) were extracted and determined respectively by this developed method, and recoveries ranging from 83.0% to 89.1% were obtained. Finally, this method was applied to quantitative detection of acrylamide in bread crust and cracker samples.

With high sensitivity and pre-treatment simplicity, this SPE-HPLC method could provide a new tool for the rapid determination of acrylamide in the food samples.