Recursive evolving spectral projection for revealing the concentration windows of overlapping peaks in two-way chromatographic experiments

The successful resolution of overlapping chromatographic peaks using multivariate resolution methods depends on information about the concentration windows of all the chemical components being available. When conventional methods based on evolving factor analysis are used to obtain such information, a problem arises as a consequence of there not being a one-to-one correspondence between the rank maps and the elution patterns. The recursive evolving spectral projection (RESP) methodology developed in this paper offers a solution to this problem. The algorithm is initialized with a gross partition of the whole retention time region into several exclusive forward or backward informative regions. After selecting a representative spectrum from every informative region, the concentration windows of the overlapping components are determined by examining the residual plots obtained from the proposed recursive evolving spectral projection procedure. Both theoretical and experimental results demonstrate that RESP possesses the characteristics of easy implementation and good performance, which will help realize the automation of non-iterative multivariate resolution methods. (C) 2004 Elsevier B.V. All rights reserved.