LCGC Europe-02-01-2016
The Chromatographic Society’s: Advances in Microcolumn and Related Separation Technologies
February 22nd 2016The first meeting of The Chromatographic Society’s Diamond Jubilee celebration year will be held at the Institute of Engineering and Technology (IET) in Savoy Place, London, UK, on Tuesday 22 March 2016.
Mechanisms of Interaction Responsible for Alternative Selectivity of Fluorinated Stationary Phases
February 1st 2016Fluorinated stationary phases, especially those including a pentafluorophenyl (PFP) moiety, have become popular alternatives to the more traditional alkyl (C8 and C18) phases. Many modern column lines have, in fact, been initially introduced with the standard C18 and a PFP phase because of their orthogonality. In this instalment, the differences between alkyl phases and PFP phases are discussed in terms of fundamental interactions. The origin of the interactions is also interpreted to better understand how analysts can use and control them to develop effective and rugged analytical methods.
The Rise of Hydrophilic Interaction Chromatography in Untargeted Clinical Metabolomics
January 31st 2016Hydrophilic interaction chromatography (HILIC) was introduced more than two decades ago and has garnered much attention. Characterized by a hydrophilic stationary phase used in combination with an aqueous organic mobile phase, numerous improvements have been achieved and HILIC is now considered as an attractive alternative to reversed-phase phase liquid chromatography (LC) for many applications. HILIC provides several advantages over reversed-phase LC for the analysis of polar compounds, including higher retention of polar metabolites, enhanced mass spectrometric sensitivity, moderate back-pressure - even at high flow rates, or when used with sub-2-µm particle size - and orthogonal selectivity. Several important technical developments have been proposed during the last decade that foster its use in metabolomics. This review presents an overview of the most recent technical improvements and applications of HILIC analysis in untargeted clinical metabolomics and discusses important practical considerations, including the selection of the optimal column chemistry, appropriate eluents, sample preparation, and data analysis.
