Graphene Modified Carbon Electrode Research Articles

Electrodeposition of bismuth at a graphene modified carbon electrode and its application as an easily regenerated sensor for the electrochemical determination of the antimicrobial drug metronidazole

Metronidazole is a well-known antimicrobial drug that belongs to the nitroimidazole family of antibiotics. It has been widely used in the treatment of infections, but its accumulation in aquatic environments is an emerging concern. In this study a glassy carbon electrode was modified with graphene (Gr) nanoplatelets and bismuth. Both the Gr and Bi were electrochemically deposited onto the glassy carbon and the modified electrode was employed in the electrochemical detection of metronidazole. At the modified electrode, the reduction of metronidazole was found to be an adsorption-controlled reaction. The optimised sensor, which was fabricated within 6 min, exhibited good selectivity in the presence of various inorganic and organic compounds, good recovery in tap water, and exhibited a linear calibration curve extending from 0.005 to 260 μM, with a limit of detection of 0.9 nM. The sensor was easily regenerated through the simple oxidation of the Bi deposit followed by a 100 s reduction period in the Bi(III) solution to give a newly generated surface. Good reproducibility was achieved using this simple regeneration approach.

Fabrication of electrochemical carbon-based microelectrodes using electrohydrodynamic jet printing technique

Due to unique advantages, carbon is widely used as electrode material for electrochemical sensors. In this paper, an efficient method of combining the electrohydrodynamic jet (E-jet) printing with the lift-off process was presented to produce the carbon-based three-electrode plate. The metal pattern was formed by lift-off process. Then the carbon pattern was printed on the metal layer by E-jet. Moreover, a graphene layer was printed on the carbon layer to improve the sensing performance by E-jet and the effect of scanning rate on thickness and density of layer was investigated. At last, an electrochemical sensor was developed with the well-made three-electrode plate and utilized to detect the samples of potassium ferricyanide and nicotinamide adenine dinucleotide. The results showed that a lower anodic peak potential was obtained in the graphene-modified carbon electrode than that of the bare carbon electrode. And in the electrochemical measurement of potassium ferricyanide, the graphene-modified electrode can decrease the potential distance between the anodic peak and the cathodic peak. It implied that the additional graphene-nanosheets can increase the reactive area and the capability of electronic conduction, thereby making the EC reaction easier to occur.

An imprinted electrochemical sensor for bisphenol A determination based on electrodeposition of a graphene and Ag nanoparticle modified carbon electrode

A highly sensitive and selective imprinted electrochemical sensor based on a Ag nanoparticle and graphene modified carbon electrode was prepared for the determination of bisphenol A in aqueous solution.