Wavelet transform and its applications in high performance liquid chromatography (HPLC) analysis

Wavelet transform has been proven to be a high performance signal processin g technique. In this paper, a novel algorithm which is more suitable to pro cess analytical signals is proposed, and application of the algorithm in de noising, baseline correction, determination of component number in overlapp ing chromatograms, and preprocessing the data matrix for window factor anal ysis (WFA) in resolving multi-component overlapping chromatograms is report ed. The main characteristic of the wavelet transform is that it decomposes a signal into localized contributions, and each of the contributions repres ents the information of different frequency contained in the original signa l. Therefore, the noise can be filtered by separating the high frequency co ntributions from the chromatogram, the baseline correction can be obtained by removing the low frequency contributions from the chromatogram, and the resolved chromatogram can be retrieved from the overlapping signal by choos ing a discrete detail at certain scales from the decomposed contributions. The determination of component number in overlapping chromatograms can be o btained by simply counting the number of peaks in the resolved chromatogram . (C) 1999 Elsevier Science B.V. All rights reserved.