Pure column or row techniques

Pure variables are fully selective for one of the factors. This means that only one pure factor contributes to the values of that variable. When the pure variables or selective wavelengths for each factor are known then the pure spectra can be calculated in a straightforward memner from the mixture spectra by solving  

The pure variable technique can be applied in the column space (wavelength) as well as in the row space (time). When applied in the column space, a pure column is one of the column factors. In LC-DAD this is the elution profile of the compound which contains that selective wavelength in its spectrum. When applied in the row space, a pure row is a pure spectrum measured in a zone where only one compound elutes. 

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