Graphite paste

Graph t-kohle, /. graphitic carbon, -masse, /. graphite paste, -pulver, n. graphite powder. 

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]. 

The resistance was measured with the standard dc four-probe method with 10pm platinum wire and graphite paste, 10-100pA current and temperatures down to 1.5K. 

Electrodes made with carbon or graphite paste mixed with a hydro-phobic diluent such as Nujol, paraffin, silicone rubber, epoxy resin, Teflon, or Kel-F, have also been used. Comparative studies between the various types of carbon paste electrode have been carried out11. 

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... 

Matuszewski, W. Trojanowicz, M., Graphite paste based enzymatic glucose electrode for flow injection analysis, Analyst 1988, 113, 735-738... 

Ion-selective electrodes with a liquid membrane are more reliable than ion-selective electrodes with a solid membrane because of the uniformity of the active material partition in the membrane. For the construction of biosensors the maximum reliability is obtained by using graphite paste as the support. As of the present, for in vivo tests only sensors based on plastic membranes have been used. The main problem associated with using them for in vivo tests is the biocompatibility of the materials.147 149 The membrane biocompatibility, the matrix biocompatibility, and the electroactive material biocompatibility are important factors. The matrix biocompatibility is assured by the biocompatibility of the polymer and by the biocompatibility of the plasticizer. The ratio between the quantity of polymer and quantity of plasticizer affects the response of electrochemical sensors because the matrix of the solid membrane electrodes plays the same role as does the solvent in liquid membrane electrodes. 

Tooling Lubricants Fligh temperature lubricants such as graphite pastes work well. 

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...

Hydroquinone Sweet potato Peroxidase Graphite paste eiectrode... 

Companies like AW Chesterton Co. use opf, in the form of 10 or 20 ply spun yarns, which are impregnated with PTFE and/or graphite pastes and when braided, produce a satisfactory packing material, suitable as an asbestos replacement, able to withstand working pressure and sustained working up to 260° C. 

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. 

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