DNA technology for small molecules sensing: a new approach for Acetamiprid detection

In this work, an electrochemical DNA aptasensor for acetamiprid is presented. The aptasensor is based on a dual signal amplified strategy by employing a gold-polyaniline modified screen-printed electrode as sensor platform and an enzyme-linked label for sensitive detection. The polyaniline-gold nanocomposite modified electrodes were firstly modified with a mixed monolayer of a thiol-tethered DNA aptamer and 6-mercapto-1-hexanol. The acetamiprid solution was then incubated with the aptasensor. An enzyme-amplified detection scheme, based on the coupling of a streptavidin-alkaline phosphatase conjugate and secondary biotinylated aptamer was then applied. The enzyme catalyzed the hydrolysis of the electroinactive 1-naphthyl-phosphate to 1-naphthol. This electroactive product was detected by means of differential pulse voltammetry. A calibration curve between 0-200 nM acetamiprid concentration range was obtained.