Advantages of Microelectrodes in Electroanalysis

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]. 

Sphere cap / = knFD(fa(4 k 2rr n2), where a = radius of the base microdisk 

Cylinder 2nFADc, i- a a-1 = where = cylinder radius roln(4Dt/r ) ° 

Band / = — tiFADr where w = band width wln(64Df/w2) 

Fast-scan voltammetry has largely been developed for biological applications [50,52], and employs scan rates up to kV s . It has also been used for the detection of various anions and cations on submillisecond timescales [32, 53-56]. 

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