Nano composite coating based on cellulose nanofibers/carbon nanoparticles: application to voltammetric determination of clonazepam

A novel electrochemical sensor for clonazepam (CLNP) was fabricated based on immobilizing cellulose nanofibers/carbon nanoparticles (CNFs/CNPs) nanocomposite on glassy carbon electrode (CNFs/CNPs/GCE). The combination of CNFs and CNPs produced a novel kind of structurally uniform and electro-analytically active nanocomposite. The surface morphology of CNFs/CNPs layer deposited onto glassy carbon electrode was characterized by scanning electron microscopy. The results of the voltammetric investigations showed a considerable enhancement in the cathodic peak current of CLNP (up to 60 times) on the surface of CNFs/CNPs/GCE relative to the bare GCE. Under the optimal conditions, the modified electrode showed a wide linear response to the concentration of CLNP in the range of 0.1–10 μM. Furthermore, high sensitivity, stability, repeatability, and reproducibility as well as low detection limit of the electrode responses can be considered as significant features of the prepared modified electrode. This sensor was successfully applied for the accurate determination of trace amounts of CLNP in pharmaceutical and clinical preparations.