Multidimensional Chromatographic Techniques for Monitoring and Characterization of Environmental Samples

Abstract

Classical one-dimensional chromatographic approaches for characterization of environmental matrices and their analytes’ monitorization, in spite of achieving valid results, may not always give satisfactory results due to a potential considerable amount of information that remains unexploited or hidden.

There is a growing use of multidimensional gas chromatography (MDGC). This is either due to the emergence of comprehensive two-dimensional gas chromatography (GC × GC) in the last decade, as a solid technique and to the recent introduction, by many GC instrument companies, of new devices capable of delivering MDGC with high accuracy (e.g., Deans switch devices and modulators), supported by hardware and software development and availability. This resurgence has been driven by the search of improved separation performance for analytes in complex samples. MDGC allows separation of complex mixtures by using multiple columns with orthogonally different stationary phases, enabling the separation of complex mixtures that cannot be separated using a single column. The heart-cut method (peak cutting and the selective transfer of peaks or chromatogram sections onto a second column) and the continuous two-dimensional chromatography (comprehensive chromatography) are the commonly used techniques in MDGC. The increased resolution and sensitivity achieved is an advantage, which would be beneficial for environmental complex samples, analytes’ monitorization, and contaminants trace analysis.