Applications biomedical electrodes

The silver-silver chloride electrode has characteristics similar to a perfectly nonpolarizable electrode and is practical for use in many biomedical applications. The electrode (Figure 4.1a) consists of a silver base structure that is coated with a layer of the ionic compound silver chloride. Some of the silver chloride when exposed to light is reduced to metallic silver hence, a typical silver-silver chloride electrode has finely divided metallic silver within a matrix of silver chloride on its surface. Because silver chloride is relatively insoluble in aqueous solutions, this surface remains stable. Moreover, because there is minimal polarization associated with this electrode, motion artifact is reduced compared to polarizable electrodes such as the platinum electrode. Furthermore, owing to the reduction in polarization, there is also a smaller effect of frequency on electrode impedance, especially at low frequencies. 

Rose TL, Robblee LS (1990) Electrical stimulation with Pt electrodes. VIII. Electrochemically stife charge injection limits with 0.2 ms pulses (neurontil application). Biomedical Engineering, IEEE Transactions on 37(11) 1118-1120, DOI 10.1109/10.61038... 

Beebe X, Rose TL (1988) Chaige injection limits of activated iridium oxide electrodes with 0.2 ms pulses in bicarbonate buffered saline (neurological stimulation application). Biomedical Engineering, IEEE Transactions on 35(6) 494-495, DOl 10.1109/10.2122... 

Franks W, Schenker I, Schmutz P, Hierlemann A (2005) Impedance characterization and modeling of electrodes for biomedical applications. Biomedical Engineering, IEEE Transactions on 52(7) 1295-1302, DOI 10.1109/TBME.2005.847523... 

Most important biomedical applications of ion-selective electrodes... 

This field is therefore at an exciting stage. Ion-selective electrodes have a proven track record in terms of clinical and biomedical analysis, with a well-developed theory and a solid history of fundamental research and practical applications. With novel directions in achieving extremely low detection limits and instrumental control of the ion extraction process this field has the opportunity to give rise to many new bioana-lytical measurement tools that may be truly useful in practical chemical analysis. 

Recently, our laboratory produced a foldable, bendable, and cutable postage-stamp-sized battery (Fig. 12.2). The device looks like a simple sheet of black paper, but it could spell a revolution in implantable battery technology (Pushparaj et al., 2007). The paper battery, a one-piece-integrated device is made of cellulose with CNT and lithium electrodes. The device is flexible, rechargeable, and has the ability to function over a wide range of temperatures giving it a wide variety of potential biomedical applications. As a biomaterial, this paper battery may be useful as a pacemaker because it could easily be inserted under a patient s skin. 

The most important applications of Ca " ISEs are in biomedical practice, especially in the determination of ionized calcium in serum. A pioneer work in this field was that by Moore [149] (see also [110,111]). At present the Ca ISE is used in the solvent polymeric version in a number of automatic devices for determining ionized calcium in serum, usually with periodic recalibration of the electrode and thermostatting to 37 °C. It should be noted that ISEs measure... 

Some applications in biomedical research and clinical medicine. Chapter 7 of Ion-Selective Electrodes (ed. R. A. Durst), NBS Special Publication No. 317, Washington (1969). 

Morf and W. Simon, Liquid membrane ion-selective electrodes and their biomedical applications. Chapter 2 of Medical and Biological Applications of Electrochemical Devices (ed. J. Koryta), John Wiley Sons, Chichester (1980). MS - mixed solution technique, SS - separate solution technique symbols for ion-exchanging ions from table 7.1. 

Research on the use of CNT-MPc based electrode in electroanalytical chemistry is still in its infancy. Without doubt, there is an enormous potential for using CNT-MPc-based electrodes for applications in areas such as environmental, industrial, food, pharmaceutical, clinical, and biomedical fields. Few studies have only been attempted with MPc complexes with Co, Fe and Ni as the central metals, meaning that there are many open doors for research on these and many other MPc complexes as redox mediators for the development of electrochemical sensors. Given the many advantages of electrochemical techniques (especially sensitivity to redox-active analytes, and amenability to automation,... 

A wide variety of parameters can directly affect the chemical and physical characteristics of a plasma, which in turn affect the surface chemistry obtained by the plasma modification. Some of the more important parameters include electrode geometry, gas type, radio frequency (0-10 ° Hz), pressure, gas flow rate, power, substrate temperature, and treatment time. The materials and plasmas used for specific biomedical applications are beyond the scope of this text, but the applications include surface modification for cardiovascular, ophthalmological, orthopedic, pharmaceutical, tissue culturing, biosensor, bioseparation, and dental applications. 

Fig. 4.6 Voltage recovery of a lithium anode at -20°C in 1 mol/dm3 LiClO in PC versus a lithium reference electrode. Current density = 10 mA/cm2. (By permission of the Electrochemical Society N. Margalit and H.J. Canning, Proceedings of the symposia on power sources for biomedical implantable applications and ambient temperature lithium batteries, eds B.B, Owens and N, Margalit, 1980, p. 339.)...

Enantioselective, potentiometric membrane electrodes design, mechanism of potential development and applications for pharmaceutical and biomedical analysis... 

Carbon products ranging from conventional materials, such as electrodes for the aluminum and steel industries, to new high-technological applications, such as biomedical implants... 

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