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HPLC peak should generally not have an asymmetry factor, B/A in figure 23-14,outside the range0.9-1.5

  1. Sketch the shape of a peak with an asymmetry of 1.8
  2. What might you do to correct the asymmetry?

Short Answer

Expert verified

HPLC peak should generally not have an asymmetry factor.

a) asymmetryfactor=3.62

asymmetryfactor=1.8

b) We can use a split injection, reduce the injection volume. increase the column thickness. A guard column or a pressure pulsed injection can also be used

Step by step solution

01

definition of Distance

When the distance from the start of the peak to the centre and the distance from the centre to the end of the peak differs, the peak is asymmetric. It is denoted by the asymmetry factor:

asymmetryfactor=BA

Where A is the distance from the start of the peak to the centre and B is the distance from the centre to the end of the peak.

If the asymmetry factor is 1.8that means that B is 1.8times greater than A. We are measuring A and B at the 110of the height of the peak

02

draw the graph

As you can see from the sketch the value of A is 2, and the value of B is 3.6 , so:

asymmetryfactor=3.62

asymmetryfactor=1.8

This sketch satisfies the given asymmetry.

b) We can use a split injection, reduce the injection volume.

increase the column thickness. A guard column or a pressure pulsed injection can also be used.

Hence,

asymmetryfactor=3.62

asymmetryfactor=1.8

b) We can use a split injection, reduce the injection volume. increase the column thickness. A guard column or a pressure pulsed injection can also be used

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