Comparative visualization for comprehensive two-dimensional gas chromatography

• Published in: Journal of Chromatography A 2006-02, Vol.1105 (1), p.51-58
• Main Authors: Hollingsworth, Benjamin V., Reichenbach, Stephen E., Tao, Qingping, Visvanathan, Arvind
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Benzene Derivatives - analysis; Chemistry; Chromatographic methods and physical methods associated with chromatography; Chromatography, Gas - methods; Comparative analysis; Comparative visualization; Comprehensive two-dimensional; Exact sciences and technology; Gas chromatographic methods; Gas chromatography; GC [formula omitted] GC; Image Processing, Computer-Assisted - methods
• ISSN: 0021-9673
• DOI: 10.1016/j.chroma.2005.11.074

This paper investigates methods for comparing datasets produced by comprehensive two-dimensional gas chromatography (GC  ×  GC). Chemical comparisons are useful for process monitoring, sample classification or identification, correlative determinations, and other important tasks. GC  ×  GC is a powerful new technology for chemical analysis, but methods for comparative visualization must address challenges posed by GC  ×  GC data: inconsistency and complexity. The approach extends conventional techniques for image comparison by utilizing specific characteristics of GC  ×  GC data and developing new methods for comparative visualization and analysis. The paper describes techniques that register (or align) GC  ×  GC datasets to remove retention-time variations; normalize intensities to remove sample amount variations; compute differences in local regions to remove slight misregistrations and differences in peak shapes; employ color (hue), intensity, and saturation to simultaneously visualize differences and values; and use tools for masking, three-dimensional visualization, and tabular presentation with controls for graphical highlights to significantly improve comparative analysis of GC  ×  GC datasets. Experimental results indicate that the comparative methods preserve chemical information and support qualitative and quantitative analyses.