cytochrome-c-t and nickel-monoxide

An amperometric biosensor for determination of Cytochrome c (Cyt c) was fabricated by immobilizing Cytochrome c oxidase (COx) onto nickel oxide nanoparticles (NiO-NPs) decorated carboxylated multiwalled carbon nanotubes/polyaniline (NiO-NPs/cMWCNT/PANI) film electrodeposited on the surface of a gold (Au) electrode. The electrochemical characteristics of immobilized COx were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Scanning Electron Microscopy (SEM) and Fourier transform Infra-red spectroscopy (FTIR). Cyclic voltammetric (CV) studies of the electrode at different stages of construction of enzyme electrode demonstrated that the modified Au electrode had enhanced electrochemical oxidation of H2O2, which offers a number of attractive features to develop amperometric biosensors based on split of H2O2. There was a good linear relationship between the current (mA) and Cyt c concentration in the range 5 x 10(-12) M to 5 x 10(-7) M. The sensor had a detection limit of 5 x 10(-12) M (S/N = 3) with a high sensitivity of 3.7 mA cm(-2) nM(-1). The sensor gave accurate and satisfactory results, when employed for determination of Cyt c in different serum samples.

Topics: Adult; Aniline Compounds; Animals; Biosensing Techniques; Cytochromes c; Electric Impedance; Electrochemical Techniques; Electrodes; Electron Transport Complex IV; Female; Goats; Gold; Humans; Limit of Detection; Male; Middle Aged; Nanotubes, Carbon; Nickel; Spectrophotometry, Ultraviolet; Spectroscopy, Fourier Transform Infrared; Temperature

This work describes the performance of cytochrome c/nickel oxide nanoparticles/glassy carbon electrode, prepared by the electrochemical deposition of the nickel oxide nanoparticles (NiO NPs) on the glassy carbon (GC) electrode surface and the cytochrome c immobilization on the nickel oxide nanoparticle surfaces. An extensive sample examination with the help of the SEM and AFM presented the existence of different geometrical shapes of the nickel oxide particles. These geometrical structures could lead to the better immobilization of proteins on their surfaces. The resulting electrode displayed an excellent behavior for the redox of the cytochrome c. Also, the resulting heme protein exhibited a direct electrical contact with the electrode because of the structural alignment of the heme protein on the nanometer-scale nickel oxide surfaces. This method could be suitable for applications to nanofabricated devices. In the end, it was concluded that the cytochrome c could be tethered to the nanometer-scale nickel oxide surfaces.

Topics: Carbon; Cytochromes c; Electrodes; Enzymes, Immobilized; Glass; Microscopy, Atomic Force; Microscopy, Electron, Scanning; Nanoparticles; Nanotechnology; Nickel; Oxidation-Reduction; Potentiometry; Surface Properties