Microelectrodes stripping analysis

Sbai M., Essis-Tome H., Gombert U., Breton T., and Pontie M., Electrochemical stripping analysis of methyl-parathion (MPT) using carbon fiber microelectrodes (CFME) modified with combinations of poly-NiTSPc and Nafion films. Sens. Actuators B, 124(2), 368-375, 2007. 

The majority of measurements for electroanalysis with microelectrodes are recorded under steady-state conditions by using either chronoamperometry (CA), linear sweep voltammetry (LSV) or cyclic voltammetry (CV) [1,2, 9,10]. Moreover, to solve problems related to the selectivity between species with similar redox potentials, pulsed techniques such as differential pulse voltammetry (DPV) [1, 7, 43 5] and square-wave voltammetry (SWV) [1, 45-49] have been employed. The use of the latter technique also minimizes the influence of oxygen in aerated natural samples [47]. In order to enhance sensitivity in these measurements, fast-scan voltammetry (FSV) [50] or the accumulation of analytes onto an electrode surface has also been performed, in conjunction with stripping analysis (SA) [51]. 

Daniele, S., Baldo, M.A. andBragato, C. (2008) Recent developments in stripping analysis on microelectrodes. Current Analytical Chemistry, 4, 215—228. 

Daniele, S. and Mazzocchin, G.A. (1993) Stripping analysis at mercury microelectrodes in the absence of supporting electrolyte. Analytica ChimicaActa, 273,3—11. 

Baldo MA, Daniele SD, Ciani I, Bragatto C, Wang J (2003) Remote stripping analysis of lead and copper by a mercury-coated platinum microelectrode. Electroanalysis 16 360-366... 

Baido MA, Daniele S, Corbetta M, Mazzocchin GA (1995) Performance of platinum-based spherical mercury microelectrodes in cyclic voltammetry and stripping analysis. Electroanalysis 7 980-986... 

Beni V, Arrigan DWM (2008) Microelectrode arrays and microfabricaled devices in electrochemical stripping analysis. Curr Anal Chem 4 229-241... 

Hanging mercury drop electrode (HMDE) A microelectrode that can concentrate traces of metals by electrolysis into a small volume the analysis is completed by voltammetric stripping of the metal from the mercury drop. 

Zhu et al. have developed a chip for heavy metal ion electrochemical detection". By controlling the microfluidics, a mercury droplet microelectrode is generated on the chip. Square wave stripping voltammetry is used for analysis. 

Strips of tissue from the SA nodal region of rabbit heart are dissected and immersed in Tyrode solution at 35°C. By subsequent cuts and ligatures a strip is reduced to a 0.25 x 0.25 mm beating preparation, which is impaled with two standard 3M KCl microelectrodes (about 40 Mohms). Voltage clamp is performed with traditional methods Voltage and current traces are recorded on a two-trace storage oscilloscope and on a 4 FM channel tape recorder for subsequent analysis... 

Voltammetric and amperometric measurements in BIA can be performed with the same electrochemical cells and detectors utilized in FIA, including wall-jet arrangement with injection of sample volume of a minimum 10 pi and the use of microelectrode arrays [104, 105]. Special attention has been attributed to the monitoring in agriculture due to the possibility of exploring portable instruments for in situ analysis. It occurs mainly through association between BIA and stripping voltammetric techniques. 

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