Geminal dicationic and polyionic ionic liquids have been prepared for use as stationary phases in capillary gas chromatography. These materials are known to provide higher thermal stability for gas chromatography, broader liquid working ranges and broader selectivity ranges than monocationic ionic liquids and polymeric based stationary phases with similar polarity. Recently, a new ionic liquid stationary phase has been developed that provides a selectivity very similar to a polyethylene glycol (PEG) selectivity but with increased thermal stability and lower bleed. We will compare and contrast the similar but unique selectivity of this new phase with traditional PEG phases using a wide variety of different sample types. We will demonstrate the improved thermal stability and lower bleed through a series of different studies and applications.Read more >
The fatty acid composition of a fat or oil is most commonly assessed by gas chromatography, following conversion of the fatty acids methyl esters. The current most refined analytical methods for the quantitation of trans fatty acids rely on the separations provided by long cyanopropyl siloxane capillary columns. The introduction of capillary columns coated with ionic liquids, such as Supelco SLB-IL111, provide an alternative separation tool characterized by a higher stationary phase polarity and selectivity toward geometric and positional isomers of unsaturated fatty acids. The use of these novel capillary columns can provide more refined separations of complex lipid samples. As a result, most conjugated linoleic acid isomers (including t7,c9- and c9,t11-18:1 FA) can be quantitated in a single separation using a 100 m SLB-IL111 capillary column and most 18:1 FA positional and geometric isomers can be separated using a 200 m SLB-IL111. Ionic liquid columns provide more detailed FA profiles, especially for unsaturated fatty acid positional/geometric isomers.Read more >
Ionic liquids (ILs) and their components have had a substantial impact on the capabilities and performance of gas chromatography, ESI-MS and MALDI-MS. For GC this ranges from the analysis of complex mixtures by GC x GC, water quantitation and food/beverage analysis among other areas. In MS the most sensitive analysis of anions, phospholipids and metal cations is often done by ESI-MS using complex IL cationic reagents. Also the best MALDI matrices for many proteins, peptides, carbohydrates and synthetic polymers are based on ILs. These will be discussed as time permits.Read more >
This webinar will provide an overview on the topic of analyzing various fatty species in foods and methods to determine various classes from total fat to various lipid fractions and the wide variety of analyses available for fat determination. Topics discussed will include the analyses of fatty acid methyl esters (FAMES) in foods and the use of comprehensive two-dimensional gas chromatography (GC x GC) for the enhanced separation of highly complex mixtures. Advances in GC column stationary phases and new phases based on ionic liquid technology for the analyses of saturated and polyunsaturated FAMES will be discussed aswell as the use of GC×GC in the field of food lipid analysis. The considerable advantages of the two-dimensional approach (both with and without MS detection), in experiments related to a series of lipid volatiles (fatty acids, sterols, oxidation products, fatty alcohols, etc) will be illustrated.
In this webinar, we will:
> Overview the wide variety of methods available for the analysis of fat in foods.
> Examine traditional and new classes of GC Stationary Phases for the evaluation of various FAME species.
> Discuss the power of two-dimensional gas chromatography (GCxGC) for separating highly complex mixtures and how it can be combined with mass spectrometry for analyzing volatile and semi-volatile analytes
Simulation software lets designers characterize their devices simply and effectively. Coupled multiphysics simulations allow the study of beam charging and current flow in imperfect dielectrics and heating effects from both primary and secondary emission. Advanced interactions can be included in simulations, such as the ionization of a background gas to form plasma ion beams.
This webinar covers modelling of a wide range of devices and physics, from simple thermal electron emission to multispecies ionic plasmas.