Surfactant adsorption surface activity/inactivity

Differential pulse polarography is particulary susceptible to surface active phenomena. Adsorbed forms of the analyte and its electrode products can give rise to separate peaks. But even the adsorption of otherwise inactive third species can alter the reversibility and electrode kinetics of the process producing sometimes huge changes in the shape of peak. The area under the peak will, however, remain constant in most cases. But the height of the peak is of no use. If surfactants are likely to be present it is best to calibrate and measure the area under the peak. 

The presence of a sharp maximum inside the inter-facial layer (Fig. IB) is characteristic of surface-active components. Siuface-inactive components can even show a minimum in the local concentration (Fig. 1C). Especially important for the stabilization of emulsions is the adsorption behavior of surfactants at the water/oil interface. To describe such systems makes it necessary to know the ad-... 

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