BASELINE CORRECTION FOR CHROMATOGRAPHY

Peak detection for a chromatogram is improved by removing systematic errors in the chromatogram using orthogonal subtraction. Orthogonal substraction involves subtracting from each spectrum in the chromatogram its expression in a spectral space representing the systematic errors. The data used in constructing the spectral space can be obtained in the form of spectra in the chromatogram occurring between component peaks. Principal component analysis can be applied to obtain a series of principal factors. A "hook method" can be applied to determine an optimum number of factors to use in constructing the spectral space, which is defined by the selected factors after normalization.