Journal of Solid State Electrochemistry   2015 年 19 卷 10 期

2015.10.01

In this work, we reported the synthesis of water-soluble carbon dots (CDs) by a one-step hydrothermal synthetic route using polyamidoamine (PAMAM) as platform and passivant, where the formation of CDs capped with PAMAM and the surface passivation were realized simultaneously. As a result, the prepared PAMAM-CDs were uniform, monodispersed sphere particles with an approximate diameter of about 2??nm, and the fluorescence and electrochemiluminescence (ECL) response of the nanocomposite film were enhanced. By combining the high sensitivity of ECL and the selectivity of immunoreactions, an ECL immunosensor for facile, rapid, and ultrasensitive detecting of ketamine was constructed, and the further application of the immunoassay was investigated. Under optimal experimental conditions, the obtained immunosensor showed a wide linear detection range from 0.2 to 200??ng??mL^??’1 with a detection limit at 0.067??ng??mL^??’1 in 0.1??M phosphate buffer solutions (pH 7.4). The immunosensor was successfully applied to the determination of ketamine in blood plasma. This kind of assay is expected to pave new avenues in label-free drug assays.