UCARE: Undergraduate Creative Activities & Research Experiences


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Spring 2016 Research Fair poster, University of Nebraska-Lincoln.


Copyright (c) 2016 Davis Rempe, Stephen Reichenbach, and Stephen Scott.


As columns age and differ between systems, retention times for GC x GC may vary between runs. In order to properly analyze chromatograms, it is often desirable to align chromatographic features between chromatograms. This alignment can be characterized by a mapping of retention times from one chromatogram to the retention times of another chromatogram. Alignment methods can be classified as global or local, i.e., whether the geometric differences between chromatograms are characterized by a single function for the entire chromatogram or by a combination of many functions for different regions of the chromatogram. Previous work has shown that global, low-degree polynomial transformation functions – namely affine, second-degree polynomial, and third-degree polynomial – are effective for aligning pairs of chromatograms acquired through GCxGC with dual secondary columns and detectors (GC x 2GC). This work assesses the experimental performance of these same methods on more general GC x GC chromatogram pairs and compares their performance to that of a recent, robust, local alignment algorithm for GC x GC data [Gros et al., Anal. Chem. 2012, 84, 9033].