Biosensor based on antifouling PEG/Gold nanoparticles composite for sensitive detection of aflatoxin M1 in milk

Abstract

Detection of ultra-trace amounts of aflatoxin M1 (AFM1) is an important requirement for food safety since it is a toxic mycotoxin, present in cow milk, with strictly regulated low levels. To achieve detection of low levels of AFM1, we developed a new nanometric aptasensing platform based on the modified SPCE, which was decorated with AuNPs, a tetraethylene glycol ferrocene derivative and an anti-AFM1 aptamer. The ferrocene tethered to AuNPs served as a capacitance transducer contributing to an interfacial charge. The capacitive signal was used to quantify the toxin. This study revealed a good sensitivity toward the toxin with a dynamic range of 20 to 300 pg·mL−1 and a LOD as low as 7.14 pg·mL−1 (S/N = 3). The nanoaptosensor exhibits very good metrological performances. To evaluate the sensing platform, the latter was applied to detect the presence of AFM1 in pasteurized cow milk.