Determination of Acrylamide in Water by Liquid Chromatography Coupled to Tandem Mass Spectrometry

Jun 01, 2014

An analytical method based on liquid chromatography coupled to tandem mass spectrometry (LC–MS–MS) has been developed for the determination of acrylamide in water. To obtain clean extracts and low detection limits, an activated carbon cartridge was investigated for use in solid-phase extraction (SPE), and extraction conditions such as desorption solvent and elution volume were optimized by a series of experiments. High recoveries (99.1–99.8%) were obtained using the activated carbon solid-phase extraction cartridges with methanol as the eluent. This method could be applied to the quantification of acrylamide in environmental water samples.

Acrylamide (1), a known neurotoxin and putative human carcinogen, has been included among the substances to be monitored in drinking water. This compound has been regulated by the European Council Directive 98/83/EC (2) with a minimum quality requirement of 0.1 µg/L in drinking water. The main source of acrylamide to drinking water is the release of residual monomer from polyacrylamide coagulants used as a clarifier in raw water treatment.

As a result of its high solubility in water (2155 g/L at 30°C) and its low levels in water, acrylamide is not easy to detect. There are very few reports on the determination of acrylamide in potable water At present, a frequently used method for the analysis of acrylamide relies on analyte derivatization and gas chromatographic (GC) separation (3). However, derivatization is often considered as time consuming, laborious, and can lead to a potential loss of analyte because of unstable or incomplete derivatization. Several groups have described a range of methods to quantify acrylamide by direct injection and reversedphase ultraviolet high performance liquid chromatography (HPLC–UV) with a limit of detection (LOD) of 5 µg/L (4) and by solidphase extraction (SPE) and gas chromatography coupled to mass spectrometry (GC–MS) analysis (5) to give limits of detection here. However, these methods are not sensitive enough for the analysis of low levels of acrylamide in water. The development of sensitive and reliable analytical methods for the quantification of acrylamide in potable water was considered as essential. The current study found that MS coupled to LC (6), using labelled acrylamide as the internal standard (IS), was now the most appropriate technique for the determination of acrylamide in water.

The purpose of this study was to develop a method for the determination of acrylamide in water at low levels. A reversed-phase LC–MS method based on a stable isotope dilution assay was developed for acrylamide analysis. Effectiveness of the enrichment process using the activated carbon cartridge for SPE was evaluated, and parameters such as desorption solvent and elution volume were optimized.