Magnetic graphene sol-gel hybrid as clean-up adsorbent for acrylamide analysis in food samples prior to GC-MS

Abstract

Graphene (G) modified with magnetite (Fe3O4) and sol–gel hybrid tetraethoxysilane-methyltrimethoxysilane (TEOS-MTMOS) was used as a clean-up adsorbent in magnetic solid phase extraction (MSPE) for direct determination of acrylamide in various food samples prior to gas chromatography-mass spectrometry analysis. Good linearity (R2 = 0.9990) was achieved for all samples using matrix-matched calibration. The limit of detection (LOD = 3 × SD/m) obtained was 0.061–2.89 µg kg-1 for the studied food samples. Native acrylamide was found to be highest in fried potato with bright-fleshed (900.81 µg kg-1) and lowest in toasted bread (5.02 µg kg-1). High acrylamide relative recovery (RR = 82.7–105.2%) of acrylamide was obtained for spiked (5 and 50 µg kg-1) food samples. The Fe3O4@G-TEOS-MTMOS is reusable up to 7 times as a clean-up adsorbent with good recovery (>85%). The presence of native acrylamide was confirmed by mass analysis at m/z = 71 ([C3H5NO]+) and m/z = 55 ([C3H3O]+).