Asymmetry Due to Overloading

In this section, we will deal with the major contributions to the asymmetry of peaks. We will first deal with asymmetry due to overloading, and then we will deal with asymmetry due to secondary interactions. 

At low concentration, there is still an approximately linear relationship between and so K is as predicted in the simple cas  

Let us consider the impact of this on chromatography by imagining ourselves in three different situations travelling down an HPLC column along with a sample of solute that has just been injected onto the column. As the band-broadening effects described previously start to become obvious, a Gaussian distribution of solute concentrations starts to develop. If there is no effect of concentration on K (a linear sorption isotherm), then all that happens is that the band continues to broaden symmetrically as it travels down the column. A symmetrical Gaussian peak will elute from the column. 

The answer to both of these problems (fronting and tailing) is discussed in Chapter 10. 

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