Latest Trends on the Future of Three-Dimensional Separations in Chromatography

Separation and characterization of complex mixtures are of crucial importance in many fields, where extremely high separation power is required. Three-dimensional separation techniques can offer a path toward achieving high peak capacities. In this Review, online three-dimensional separation systems are discussed, including three-dimensional gas chromatography, and hyphenated combinations of two-dimensional gas chromatography with liquid chromatography or supercritical-fluid chromatography. Online comprehensive two-dimensional liquid chromatography provides detailed information on complex samples and the need for higher peak capacities is pushing researchers toward online three-dimensional liquid chromatography. In this review, an overview of the various combinations are provided and we discuss and compare their potential performance, advantages, perspectives, and results obtained during the most recent 10-15 years. Finally, the Review will discuss a novel approach of spatial three-dimensional liquid separation to increase peak capacity.

Multidimensional GC coupled to MS for the simultaneous determination of oxygenate compounds and BTEX in gasoline

In the present work, carried out in relation to the European and American Directives on the quality of petrol and diesel fuels, the simultaneous determination of the oxygenate compounds and BTEX in gasoline was achieved through the use of a multidimensional GC (MDGC)/MS system, employing a Deans switch-based transfer system, with an innovative configuration; the latter enabled multiple heart-cut transfers with no hint of retention time shift, a phenomenon that can occur in MDGC, providing the possibility to achieve more then 20 different heart-cuts for the compounds of interest. In this study, 20 selected compounds were quantitatively transferred with 12 heart-cuts, from a first to a secondary column, in order to resolve primary column co-elutions. Analyte quantification and identification was achieved through a fast-scanning quadrupole mass analyzer, operated in full scan mode, in order to evaluate also the interfering compounds transferred together with the compounds of interest. The multidimensional method developed was subjected to validation. All attained data were in excellent correlation with results obtained through the UNI-EN 12177:2000, ASTM D 5580-02 and ASTM D 4815-04 MDGC methods, for the determination of benzene, BTEX and oxygenate compounds in gasoline, respectively.