4. Stripping: An excitation waveform is applied from the
polarographic analyzer which electrolyzes the deposited
material back into the solution. The current is measured
vs. the applied potential. The materials deposited in the
electrode will strip at potentials very close to their
polarographic half-wave potentials. The measured
current at these potentials is proportional to the
concentration of the analyte in the original sample. Either
a dc or a differential pulse waveform may be used during
the stripping step (see Figure 4). Curve A shows the
stripping peak for cadmium with a differential pulse
waveform. Curves B and C show the same stripping peak
with a dc waveform at different scan rates. As in
polarography, a significant increase in sensitivity is
observed when the differential pulse waveform is used.