Combining spectroscopic data (MS, IR): exploratory chemometric analysis for characterising similarity/diversity of
1ChemoAc, Pharmaceutical Institute, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium.
Abstract:
Combined infrared--mass spectra (IR--MS) have been used to examine a small data set of synthetic substances in order to elucidate whether a combination of spectral descriptors yield better classification and similarity predictions than their corresponding individual spectral descriptors. To eliminate differences in variation, a logarithmic transformation or log double-centering pretreatment was necessary. Principal component analysis (PCA) was applied to observe clusters of similar compounds. Hierarchical upgma-cluster analysis was also used for data classification.
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