Non-enzymatic acetylcholine sensor based on Ni–Al layered double hydroxides/ordered mesoporous carbon

Abstract

In this work, a novel non-enzymatic acetylcholine (ACh) sensor was constructed based on electrodepoition of Ni–Al layered double hydroxides (Ni–Al LDHs) on ordered mesoporous carbon (OMC) modified glassy carbon (GC) electrode. The obtained Ni–Al LDHs/OMC nanocomposite was characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and electrochemical methods. A novel non-enzymatic acetylcholine (ACh) sensor based on Ni–Al LDHs/OMC was developed. Compared with the pristine OMC and Ni–Al LDHs modified electrodes, Ni–Al LDHs/OMC displayed higher electrocatalytic activity toward ACh and gave a wide concentration interval of 2–4922μM and a low limit of detection (42nM, R=0.999), which is better than some reports in the literatures. The sensor also exhibited long-term stability and remarkable antifouling property. The excellent electrocatalysis for ACh can be attributed to the combination of the unique properties of Ni–Al LDHs nanoparticles and the ordered mesostructure of OMCs matrix.