Electrochemical detection technique

Therefore, hplc methods seem more effective. By usiag a combiaed uv and electrochemical detection technique (52), the gem-chlotinated cyclohexadienones, the chlorophenols, and the phenoxyphenols present ia the chlorination mixtures can be determined with great accuracy. 

Several publications describe electrochemical detection techniques, and some authors report indirect fluorescence detection and mass spectrometry detection. 

By far the most popular of the electrochemical detection techniques is am-perometric detection. Here a fixed potential is applied to the electrode, most often glassy carbon, and a solute which will oxidize (or reduce) at that potential yields an output current. Very little of the solute species, often less than 10%, is involved in the actual electron transfer process. A second method is coulometric detection. Here 100% of the solute species is converted, which offers advantages of no mobile-phase flow dependence on the signal and absolute quantitation through Faraday s law, but a large-area electrode must be used. This then makes the electrode much more susceptible to fouling, and offers no improvement in signal-... 

Another research group has created an electrochemical microdevice which supports both amplification and detection of DNA". The integrated chip houses an 8 pL reaction chamber, the associated temperature sensors and heaters and two electrochemical detection techniques, including metal complex intercalators and nanogold particles. The sensitivity of the device allows the detection of a few hundred copies of target DNA. 

Intracellular biochemistry assays were the first and continue to be the most common cell assays performed in microfluidic devices. Controllable and highly resolved delivery of reagents to cells and facile integration with optical and electrochemical detection techniques has sparked... 

The vast majority of electrochemical-detection techniques in immunoassay are based on voltammetry, the branch of electroanalysis that involves applying a potential to an electrochemical cell and measuring the current that results from oxidation or reduction at the electrode [98]. Of the many techniques of voltammetry. 

G.-A Junter, (Ed.), Electrochemical Detection Techniques in the Applied Biosciences Volume 1 Analysis and Clinical Applications, Ellis Horwood, Chichester, 1988. 

Appropriate protective membrane covering the electrode or/and modification of the electrode surface permit the operation of voltammetric sensors independently of the solution variables. This feature plays a critical role especially in reactions occurring in suspensions, emulsions or in biofluids (cf. paragraph 7.3). The application of voltammetry and polarography is discussed in monographs such as [3] or [140]. The problems of electrochemical detection techniques in clinical, biotechnological and environmental applications for the biosciences are dealt with in [141]. 

G. A. Junter (ed) in Electrochemical Detection Techniques in Applied Biosciences, E. Horwood, Chichester, 1988, Vol. I Chap. 1.1. 

K. Stulik, V. Pacakova Electrochemical Detection Techniques in High-Performance Liquid Chromatography, J. Electroanal. Chem. 129 (1981) 1. 

Monitoring of cellular d3mamics with electrochemical detection techniques... 

In this chapter, we have reported some examples related to DNA sensors, especially used in food applications, by employing electrochemical detection techniques. A variety of sensing systems based on label-free techniques utilizing electrochemical and/or surface activity as well as direct methods that rely on the intrinsic electrochemical properties of DNA (the oxidation of purine bases, particularly guanine) have been presented in the different sections of this chapter. 

Mateo-Martf, E. and Pradier, C.-M., A novel type of nucleic acid-based biosensors the use of PNA probes, associated with surface science and electrochemical detection techniques, in Intelligent and Biosensors, InTech, 2010,323-344. 

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