Development of an inner filter effect-based fluorescence immunoassay for the detection of acrylamide using 9-xanthydrol derivatization

Abstract The far-ranging occurrence of acrylamide (AA), a Group 2A carcinogen, in extensively consumed processed foodstuffs has aroused worldwide public health concern, and heightened the need for rapid and reliable detection technologies. Current immunoassays for AA are mainly based on antibodies against mercaptobenzoic acid (MBA) derivatized AA, and thus require a relatively complicated pre-analysis sample derivatization using MBA (heating > 50 °C, time>1 h), which limits the analysis efficiency. In this work, two haptens against xanthyl acrylamide (XAA) were synthesized, and a specific and high-affinity polyclonal antibody against XAA (anti-XAA pAb) was obtained. By virtue of this antibody, a fluorescence immunoassay for quantification of acrylamide with a simple sample derivatization by 9-xanthydrol (ambient temperature, 30 min) was developed via introducing the fluorescent signal of carbon dots (CDs) through the facile inner-filter eff ;ect (IFE) strategy. This fluorescence immunoassay displayed a sensitive and specific response to AA with a detection limit of 0.16 μg/L, which was lower than the legal limit in drinking water (0.5 μg/L) set by WHO. Recovery test and method validation by HPLC-MS/MS demonstrated its good accuracy and reliability, suggesting that this fluorescence immunoassay can be a potentially effective tool for the supervision of AA contamination in foods.