A dual-recognition-controlled electrochemical biosensor for selective and ultrasensitive detection of acrylamide in heat-treated carbohydrate-rich food.

A synergistic hybrid was fabricated for the electrochemical aptasensing of acrylamide (AAM) via molecularly imprinted technology. The aptasensor depends on the modification of glassy carbon electrode with AuNPs and reduced graphene oxide (rGO)/multiwalled carbon nanotubes (MWCNTs) {Au@rGO-MWCNTs/GCE}. The aptamer (Apt-SH) and AAM (template) were incubated with the electrode. After that, the monomer was electro-polymerized to fabricate molecular imprinted polymeric film (MIP) over the surface of Apt-SH/Au@rGO/MWCNTs/GCE. The modified electrodes were characterized using different morphological and electrochemical techniques. Under optimum conditions, the aptasensor exhibited a linear relationship between AAM concentration and anodic peak current difference (ΔIpa) in the range of 1-600 nM with a limit of quantitation (LOQ, S/N = 10) and a limit of detection (LOD, S/N = 3) of 0.346 and 0.104 nM, respectively. The aptasensor was successfully applied for the determination of AAM in potato fries samples with recoveries % in the range of 98.7-103.4 % and RSDs did not exceed 3.2 %. The advantages of MIP/Apt-SH/Au@rGO/MWCNTs/GCE are low detection limit, high selectivity, and satisfactory stability towards AAM detection.