Graphite paste electrodes

P.C. Pandey, S. Upadhyay, N.K. Shukla, and S. Sharma, Studies on the electrochemical performance of glucose biosensor based on ferrocene encapsulated ORMOSIL and glucose oxidase modified graphite paste electrode. Biosens. Bioelectron. 18,1257—1268 (2003). 

The graphite paste electrode, introduced into voltammetry by Adams [1], has an analogue in an ISE where a mixture of graphite powder with an ion-exchanger solution functions as the electrode membrane, into which a platinum contact is immersed [16, 129, 149]. 

Nujol — Mineral oil that is frequently used as binder for graphite paste electrodes. Colorless liquid, boiling point 179-210°C, specific density 0.752gem-3, vapor pressure 2 psi at 21.2 °C. CAS No 8020-83-5. 

Although enzymes with deeply embedded active centers do not normally allow significant non-mediated electron transfer [44], under carefully chosen conditions direct electron transfer is possible, and has been reported for glucose oxidase (GOx) at a bare Ag electrode [45] and in graphite paste electrodes [46]. These systems are unusual and the nonmediated mechanism of such long-range electron transfer is not fully understood. 

Electrode materials Pt. platinum PG. pyrographite AC, active carbon GC. glasslike carbon CF. carbon fiber. CCEs, ceramic carbon electrodes CPE. carbon (graphite) paste electrode Soim e-. Refs. 12, 201. and 206-221... 

Randey R. C., Upadhyay S., Rathak H. C., Randey C. M. D., and Tiwari I., Acetylthiocholine/acetylcholine and thiocholine/choline electrochemical biosensors/ sensors based on an organically modified sol-gel glass enzyme reactor and graphite paste electrode. Sens. Actuators B, 62(2), 109-116, 2000. 

Figure 11. Cyclic voltamograms of some of the anilines. Sweep rate 50 mV/s graphite paste electrode, Ag/AgCl reference electrode. The solvent was 50/50 acetonitrile/phosphate buffer, and the concentration was 0.1 mg/mL. Note that the oxidation potential of the aminochlorophenol is much lower than the anilines...

Afkhami et al. [162] used a graphite paste electrode containing MWCNT modified by the electrodeposition of gold NPs from a HAuCl solution to successfully determine cefixime, methadone [163], and nitrite [164] in a pharmaceutical form, in urine and saliva in several food stuffs and water samples, respectively. Fe203... 

J., Fatibello-Filho, O, and Banks, C.E. (2013) Exploring the electrochemical performance of graphitic paste electrodes graphene vs. graphite. Analyst, 138, 6354- 6364. 

In liquid chromatography applications, with a predetermined potential at the WE and just column eluent flowing, only residual current is observed. (In chromatographic parlance this is often called standing current.) Especially when a new graphite paste electrode is first used, the residual current may be large. One or two hours of operation with the potential applied and eluent pumping may be required before the residual current decreases to a stable condition. 

Volikakis, G. J. and C. E. Efstathiou. 2000. Determination of rutin and other flavonoids by flow-injection/adsorptive stripping voltammetry using nujol-graphite and diphenylether-graphite paste electrodes. Talanta 51(4) 775-785. 

Rice, M.E., Z. Gains, and R.N. Adams, Graphite paste electrodes Effects of paste composition and surface states on electron-transfer rates. Journal of Eleetroanalytical Chemistry and Interfacial Electrochemistry, 1983. 745(1-2) p. 89-102. 

Fig. 65. A holder for graphite paste electrodes (a) A standard taper glass joint (6) A Teflon plug (c) A platinum or copper wire (d) The carbon paste.

Trojanowicz M, Matuszewski W (1989) Potentiometric stripping determination of nickel at a dimethylglyoxime-containing graphite paste electrode. Talanta 36 680-682... 

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