An ultrasensitive electrochemical aptasensor based on hydroxylated black phosphorus/thionine/poly-l-lysine nanocomposite for acetamiprid detection.

A highly sensitive aptamer electrochemical sensor based on hydroxylated black phosphorus /thionine/poly- l -lysine (hBP/TH/PLL) nanocomposite and Au nanoparticles (Au NPs) was herein introduced for detection of Acetamiprid. The hBP/TH/PLL nanocomposite was prepared through the capping effect of thionine and adhesion property of poly- l -lysine (PLL). The nanocomposite can maintain excellent electrical conductivity of black phosphorus and effectively prevent oxidation of black phosphorus. The sensor was based on hBP/TH/PLL composite and AuNPs, and used highly specific aptamers as sensor probes. It has advantages such as low detection limit, high selectivity, great repeatability and stability. Under optimum conditions, the linear range of aptamer electrochemical sensor is 10 fM to 1 μM and detection limit is 9.407 fM. The aptamer electrochemical sensor has great selectivity and anti-interference, and has a potential application prospect in the field of rapid trace detection of pesticide residues. [ABSTRACT FROM AUTHOR]