A novel electrochemiluminescence aptasensor for sensitive detection of kanamycin based on the synergistic enhancement effects between black phosphorus quantum dots and silver-decorated high-luminescence polydopamine nanospheres.

Black phosphorus quantum dots (BPQDs), as a new type of nanomaterial, have excellent electrical and optical properties. In this work, an efficient monitoring method for kanamycin (KAN) was developed based on a sensitive and selective electrochemiluminescence (ECL) aptasensor. The construction of the ECL illuminant was based on BPQDs loaded on silver-nanoparticle modified high-luminescence polydopamine nanospheres (HLPNs@Ag). HLPNs possessed a large specific surface area and strong adhesion, which could support a great deal of BPQDs. Meanwhile, Ag NPs could accelerate the electron-transfer (ET) rate of the sensor and amplify the ECL signal of the BPQDs. Based on the synergistic enhancement effects between the above materials, the as-fabricated nanocomposites exhibited superior ECL performance. With the assistance of a KAN aptamer, the sensor can detect KAN sensitively and selectively. Under optimal conditions, the aptasensor could detect KAN in a wide linear range from 1 × 10-12 to 1.0 × 10-7 M with a detection limit of 1.7 × 10-13 M (S/N = 3). More importantly, this ultra-sensitive and rapid ECL aptasensor-based KAN detection system provided excellent applicability for the monitoring of environmental safety.