Square-wave amplitude current components

The second procedure is based on the effect of the square wave amplitude on the peak potential separation between the anodic and cathodic components of the SWV response. This separation depends on both the reversibility of the surface charge transfer (through co and Sw- Thus, by plotting the differences AEp = Epc — E pl>, with Ep c and EpA being the peak potentials of the forward and reverse currents measured versus the index potential, or AE p = Ef c — E p a with h p c and h p a being the peak potentials of the forward and reverse currents measured versus the real potential that is applied in each case (potential-corrected voltammograms), it is possible to obtain linear dependences between the peak potentials separation and... 

The peak currents and potentials of the forward and backward components are listed in Table II.3.2. If the square-wave amplitude is not too small nEsw > 10 mV), the backward component indicates the reversibility of the electrode reaction. In the... 

Table 2.1 Square-wave voltammetry of fast and reversible electrode reaction (1.1). The dimensionless net peak current, the ratio of peak currents of the forward and backward components, the peak potentials of the components and the half-peak width as functions of SW amplitude ...

Neurostimulation is usually performed with needles, and square wave pulses of amplitude <5 mA and duration <1 ms are common. Nerve stimulators may be with or without a net DC component. With skin surface electrodes, the current used may be larger. 

As the name implies, this voltammetric technique involves the square-wave potential component of a small amplitude (see Fig. 30). This form of superimposed potential enables the elimination of the capacitive current in an analogous way as is done in other pulse methods. 

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