Sampled-current voltammetry continued

Actually one need not even apply steps. It is satisfactory to change the potential linearly with time and to record the current continuously, as long as the rate of change is small compared to the rate of adjustment in the steady state. Section 6.2.3 contains a discussion of the required conditions in more quantitative terms. Virtually all sampled current voltammetry at UMEs is carried out experimentally in this linear-sweep form, but the results are the same as if a normal sampled-current voltammetric protocol were employed, except with respect to the charging-current background [see Sections 6.2.4 and 7.3.2(c)]. 

There is another characteristic that all these techniques present the current is sampled at a given moment during the application of any individual potential of the sequence (typically at the end of each applied potential), so the response is a discrete collection of pairs of data (potential-current). Conversely, in the case of techniques like Linear Sweep Voltammetry or Cyclic Voltammetry, the current is recorded continuously (see Sect. 5.1).11... 

Detection limits reach ca 1 nM when background or capacitive currents are filtered or compensated, in transient methods such as differential pulse polarography (DPP) or voltammetry. Numerous redox molecules, either metabolites or drugs, may be determined in biological samples either directly or after an extraction procedure[3,4]. Particularly miniaturized electrodes using carbon fibers or paste may be implanted and allow the continuous monitoring of some metabolites and drugs in neuronal tissues or arteries[5-8]. 

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