Troubleshooting guide

Lab Exercise: Qualitative Data Analysis

Peak Purity

The Peak Purity algorithm can help you determine whether a chromatographic

peak is comprised of one or more components. In quality control, impurities

hidden behind the peak of interest can falsify results. In research, a hidden

component left undetected might lead to a loss of essential information.

1) In the Methods ChemStation Explorer, find DEF_LC.M and load the method

by double-clicking on the name.

2) In the Data ChemStation Explorer, double-click on the Single Runs found

under the Demo folder to load the files into the Navigation Table.

3) Load one signal from DEMODAD.D. Now go to the Spectra menu and

choose Select Peak Purity. In this exercise, you will use the default purity

options. Alternatively, use the tools.

4) Click on a major chromatographic peak. Examine the resulting displays.

Compare your results to that of the pure and impure peaks presented in the

lecture. Make sure you compare the Purity Factor and the calculated

Threshold found by selecting the Information on the LC Peak Purity Tool.

5) Select three major peaks and answer the questions below. To review another

chromatographic peak, simply click on the peak in the chromatogram located

in the upper portion of the purity display.