Design of an electrochemical aptasensor based on porous nickel-cobalt phosphide nanodiscs for the impedimetric determination of ractopamine

A trend in the development of aptasensors is introducing high-performance nanomaterials as a platform of biosensors with suitable aptamer binding capacity and good electrochemical activity. Here, for the first time, we report the application of nickel-cobalt phosphide nanodiscs (NiCo-P NDs) in the design of an aptasensor for the impedimetric determination of ractopamine (RAC). The highly porous NiCo-P NDs were synthesized by a simple two-step method. Due to the high porosity and large specific surface area of NiCo-P NDs, it increases the loading of the aptamers on the modified electrode and improves the performance of the proposed aptasensor. Under optimal conditions, the designed aptasensor could determine RAC in a wide linear concentration range from 0.50 f. to 1.25 mu M and has an ultralow limit of detection (LOD) of 166 aM (S/N = 3). The fabricated electrochemical aptassensor is reproducible, selective, cast-effective, which was successfully used to RAC detection in blood serum samples. We hope that our study will develop the application of the multi-metal phosphide nanodiscs in biosensing devices.