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Recent developments in the manufacturing of high performance liquid chromatography stationary phases have created polar stationary phases that have the ability to retain certain polar species. However, these stationary phases still require highly aqueous mobile phases, which cause reduced mass spectrometry (MS) sensitivity. Hydrophilic interaction liquid chromatography (HILIC), which uses a polar stationary phase, has proved to be an effective approach in improving MS sensitivity, while presenting certain drawbacks. Porous graphitic carbon can retain very polar and ionic species as well as hydrophobic analytes. Here we focus on the challenges faced with the retention of "problematic" polar species and consider the options available for their analysis. [ABSTRACT FROM AUTHOR]

The article presents a study on the use of pentafluorophenyl (PFP) reverse phase column in the High Performance Liquid Chromatography (HPLC) separation of 30 perfluorinated compounds (PFC) and isomers in the U.S. in 2011. It notes the performance of PFC analysis through a binary HPLC pump couple with a triple quadrupole mass spectrometry (MS) sytem. It reveals the modification of elution using the Hypersil GOLD PFP column in helping separate the majority of the compounds.

The article presents a study on gas chromatography column selection for the analysis of volatiles and higher alcohols in whisky. It presents the method utilized in the study wherein whisky analysis has traditionally been carried out using polar and wax type column. The results show positive and negative effect wherein the advantage of the wax type column is better peak shape and being well established in the type of analysis while the disadvantage is the co-elution of the low polarity compounds.

This article reports that limitations in the current use of 3- and 5-μm particles in high performance liquid chromatography has lead to interesting theories of how an expanded van Deemter curve can be utilized with smaller particles to increase efficiency and analysis speed. Columns packed with small particles can be operated over a wide flow-rate range, maintaining high efficiencies. Therefore, these high efficiencies enable considerable improvements in speed of analysis or in resolution. To ensure that this increase in efficiency can be converted into an increase in speed of analysis without a loss in resolution, excellent peak shapes must also be achieved. The 1.9-μm particles used in this study are built on the latest silica and bonding technology of Hypersil GOLD, already acclaimed to give excellent peaks shapes for basic pharmaceutical analytes.

This article reports that the main benefits of increased temperature are shorter retention times and a general improvement in peak efficiency and peak asymmetry. Ultra high temperature liquid chromatography (UHT-LC) is expected to show advantages when coupled with mass spectrometry. When UHT-LC is used in combination with atmospheric-pressure chemical ionization, the mobile phase reaches the ion source at elevated temperature, which should assist in the vaporization and desolvation processes, thus increasing the ionization efficiency and consequently the sensitivity of the analysis.