Chromatography

Many applications in comprehensive GCxGC/MS relate to fi nding diff erences between a newly measured sample and

a so-called reference sample. Th ese questions may typically arise in application areas like product control or during

trouble shooting. Examples are: what are the new impurities present in a new batch compared to a reference batch?; why does

this product behave diff erently compared to our reference batch? And; the comparison of samples in food fraud applications

to detect illegally added substances. Typically for the above examples is the limited time available to solve these problems.

Furthermore, most of the time only a few samples are available, which excludes the use of statistical comparison tools as

applied in the fi eld of metabolomics. Although GCxGC-MS has become an invaluable laboratory analysis tool, the procedure

may produce gigabytes of data per sample in four dimensions, which makes data analysis time consuming and complicated. In

the presentation, new methods and soft ware tools will be presented to quickly fi nd diff erential components from a comparison

between two samples only. Certainly, comprehensive GCxGC/MS is a technique having superior separation capabilities

compared to 1-dimensional GC/MS, but co-elution or near co-elution still might occur, especially in complicated matrices.

Whereas most soft ware tools for GCxGC/MS use processing of “TIC” data only, our new methods apply data analysis using

the “all ions” approach. Th e implemented method allows for the detection and de-convolution of diff erential components

that are not or badly separated, even in two dimensions. It will be demonstrated that processing using the “all ion” approach

will substantially detect more (diff erential) components, compared to the analysis using TIC data only. Technical details of

the algorithms will be explained and examples will be given from applications like food analysis, product control in fl avor &

fragrance industry and from base chemistry industry.